jdk/src/share/classes/java/lang/invoke/MethodHandles.java
author rriggs
Thu, 17 Oct 2013 13:43:46 -0400
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parent 20853 505b28fe2b98
child 21362 8b2d68e8632a
permissions -rw-r--r--
8026183: minor documentation problems in java.lang.invoke 8015808: Typo in MethodHandle javadoc Summary: Fix typos and javadoc markup and extraneous paragraph tags Reviewed-by: lancea
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/*
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 * Copyright (c) 2008, 2013, Oracle and/or its affiliates. All rights reserved.
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
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 * This code is free software; you can redistribute it and/or modify it
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 * under the terms of the GNU General Public License version 2 only, as
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 * published by the Free Software Foundation.  Oracle designates this
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 * particular file as subject to the "Classpath" exception as provided
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 * by Oracle in the LICENSE file that accompanied this code.
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 *
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 * This code is distributed in the hope that it will be useful, but WITHOUT
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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 * version 2 for more details (a copy is included in the LICENSE file that
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 * accompanied this code).
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 *
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 * You should have received a copy of the GNU General Public License version
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 * 2 along with this work; if not, write to the Free Software Foundation,
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 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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 *
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 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 * or visit www.oracle.com if you need additional information or have any
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 * questions.
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 */
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package java.lang.invoke;
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import java.lang.reflect.*;
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import java.util.List;
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import java.util.ArrayList;
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import java.util.Arrays;
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import sun.invoke.util.ValueConversions;
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import sun.invoke.util.VerifyAccess;
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import sun.invoke.util.Wrapper;
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import sun.reflect.CallerSensitive;
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import sun.reflect.Reflection;
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import sun.reflect.misc.ReflectUtil;
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import sun.security.util.SecurityConstants;
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import static java.lang.invoke.MethodHandleStatics.*;
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import static java.lang.invoke.MethodHandleNatives.Constants.*;
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import java.util.concurrent.ConcurrentHashMap;
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import sun.security.util.SecurityConstants;
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/**
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 * This class consists exclusively of static methods that operate on or return
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 * method handles. They fall into several categories:
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 * <ul>
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 * <li>Lookup methods which help create method handles for methods and fields.
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 * <li>Combinator methods, which combine or transform pre-existing method handles into new ones.
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 * <li>Other factory methods to create method handles that emulate other common JVM operations or control flow patterns.
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 * </ul>
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 * <p>
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 * @author John Rose, JSR 292 EG
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 * @since 1.7
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 */
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public class MethodHandles {
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    private MethodHandles() { }  // do not instantiate
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    private static final MemberName.Factory IMPL_NAMES = MemberName.getFactory();
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    static { MethodHandleImpl.initStatics(); }
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    // See IMPL_LOOKUP below.
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    //// Method handle creation from ordinary methods.
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    /**
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     * Returns a {@link Lookup lookup object} with
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     * full capabilities to emulate all supported bytecode behaviors of the caller.
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     * These capabilities include <a href="MethodHandles.Lookup.html#privacc">private access</a> to the caller.
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     * Factory methods on the lookup object can create
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     * <a href="MethodHandleInfo.html#directmh">direct method handles</a>
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     * for any member that the caller has access to via bytecodes,
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     * including protected and private fields and methods.
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     * This lookup object is a <em>capability</em> which may be delegated to trusted agents.
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     * Do not store it in place where untrusted code can access it.
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     * <p>
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     * This method is caller sensitive, which means that it may return different
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     * values to different callers.
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     * <p>
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     * For any given caller class {@code C}, the lookup object returned by this call
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     * has equivalent capabilities to any lookup object
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     * supplied by the JVM to the bootstrap method of an
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     * <a href="package-summary.html#indyinsn">invokedynamic instruction</a>
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     * executing in the same caller class {@code C}.
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     * @return a lookup object for the caller of this method, with private access
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     */
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    @CallerSensitive
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    public static Lookup lookup() {
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        return new Lookup(Reflection.getCallerClass());
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    }
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    /**
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     * Returns a {@link Lookup lookup object} which is trusted minimally.
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     * It can only be used to create method handles to
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     * publicly accessible fields and methods.
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     * <p>
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     * As a matter of pure convention, the {@linkplain Lookup#lookupClass lookup class}
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     * of this lookup object will be {@link java.lang.Object}.
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     *
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     * <p style="font-size:smaller;">
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     * <em>Discussion:</em>
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     * The lookup class can be changed to any other class {@code C} using an expression of the form
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     * {@link Lookup#in publicLookup().in(C.class)}.
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     * Since all classes have equal access to public names,
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     * such a change would confer no new access rights.
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     * A public lookup object is always subject to
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     * <a href="MethodHandles.Lookup.html#secmgr">security manager checks</a>.
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     * Also, it cannot access
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     * <a href="MethodHandles.Lookup.html#callsens">caller sensitive methods</a>.
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     * @return a lookup object which is trusted minimally
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     */
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    public static Lookup publicLookup() {
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        return Lookup.PUBLIC_LOOKUP;
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    }
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    /**
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     * Performs an unchecked "crack" of a
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     * <a href="MethodHandleInfo.html#directmh">direct method handle</a>.
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     * The result is as if the user had obtained a lookup object capable enough
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     * to crack the target method handle, called
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     * {@link java.lang.invoke.MethodHandles.Lookup#revealDirect Lookup.revealDirect}
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     * on the target to obtain its symbolic reference, and then called
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     * {@link java.lang.invoke.MethodHandleInfo#reflectAs MethodHandleInfo.reflectAs}
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     * to resolve the symbolic reference to a member.
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     * <p>
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     * If there is a security manager, its {@code checkPermission} method
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     * is called with a {@code ReflectPermission("suppressAccessChecks")} permission.
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     * @param <T> the desired type of the result, either {@link Member} or a subtype
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     * @param target a direct method handle to crack into symbolic reference components
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     * @param expected a class object representing the desired result type {@code T}
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     * @return a reference to the method, constructor, or field object
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     * @exception SecurityException if the caller is not privileged to call {@code setAccessible}
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     * @exception NullPointerException if either argument is {@code null}
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     * @exception IllegalArgumentException if the target is not a direct method handle
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     * @exception ClassCastException if the member is not of the expected type
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     * @since 1.8
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     */
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    public static <T extends Member> T
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    reflectAs(Class<T> expected, MethodHandle target) {
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        SecurityManager smgr = System.getSecurityManager();
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        if (smgr != null)  smgr.checkPermission(ACCESS_PERMISSION);
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        Lookup lookup = Lookup.IMPL_LOOKUP;  // use maximally privileged lookup
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        return lookup.revealDirect(target).reflectAs(expected, lookup);
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    }
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    // Copied from AccessibleObject, as used by Method.setAccessible, etc.:
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    static final private java.security.Permission ACCESS_PERMISSION =
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        new ReflectPermission("suppressAccessChecks");
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    /**
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     * A <em>lookup object</em> is a factory for creating method handles,
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     * when the creation requires access checking.
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     * Method handles do not perform
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     * access checks when they are called, but rather when they are created.
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     * Therefore, method handle access
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     * restrictions must be enforced when a method handle is created.
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     * The caller class against which those restrictions are enforced
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     * is known as the {@linkplain #lookupClass lookup class}.
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     * <p>
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     * A lookup class which needs to create method handles will call
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     * {@link MethodHandles#lookup MethodHandles.lookup} to create a factory for itself.
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     * When the {@code Lookup} factory object is created, the identity of the lookup class is
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     * determined, and securely stored in the {@code Lookup} object.
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     * The lookup class (or its delegates) may then use factory methods
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     * on the {@code Lookup} object to create method handles for access-checked members.
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     * This includes all methods, constructors, and fields which are allowed to the lookup class,
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     * even private ones.
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     *
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     * <h1><a name="lookups"></a>Lookup Factory Methods</h1>
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     * The factory methods on a {@code Lookup} object correspond to all major
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     * use cases for methods, constructors, and fields.
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     * Each method handle created by a factory method is the functional
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     * equivalent of a particular <em>bytecode behavior</em>.
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     * (Bytecode behaviors are described in section 5.4.3.5 of the Java Virtual Machine Specification.)
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     * Here is a summary of the correspondence between these factory methods and
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     * the behavior the resulting method handles:
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     * <table border=1 cellpadding=5 summary="lookup method behaviors">
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     * <tr>
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     *     <th><a name="equiv"></a>lookup expression</th>
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     *     <th>member</th>
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     *     <th>bytecode behavior</th>
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     * </tr>
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     * <tr>
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     *     <td>{@link java.lang.invoke.MethodHandles.Lookup#findGetter lookup.findGetter(C.class,"f",FT.class)}</td>
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     *     <td>{@code FT f;}</td><td>{@code (T) this.f;}</td>
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     * </tr>
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     * <tr>
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     *     <td>{@link java.lang.invoke.MethodHandles.Lookup#findStaticGetter lookup.findStaticGetter(C.class,"f",FT.class)}</td>
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     *     <td>{@code static}<br>{@code FT f;}</td><td>{@code (T) C.f;}</td>
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     * </tr>
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     * <tr>
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     *     <td>{@link java.lang.invoke.MethodHandles.Lookup#findSetter lookup.findSetter(C.class,"f",FT.class)}</td>
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     *     <td>{@code FT f;}</td><td>{@code this.f = x;}</td>
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     * </tr>
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     * <tr>
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     *     <td>{@link java.lang.invoke.MethodHandles.Lookup#findStaticSetter lookup.findStaticSetter(C.class,"f",FT.class)}</td>
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     *     <td>{@code static}<br>{@code FT f;}</td><td>{@code C.f = arg;}</td>
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     * </tr>
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     * <tr>
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     *     <td>{@link java.lang.invoke.MethodHandles.Lookup#findVirtual lookup.findVirtual(C.class,"m",MT)}</td>
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     *     <td>{@code T m(A*);}</td><td>{@code (T) this.m(arg*);}</td>
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     * </tr>
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     * <tr>
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     *     <td>{@link java.lang.invoke.MethodHandles.Lookup#findStatic lookup.findStatic(C.class,"m",MT)}</td>
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     *     <td>{@code static}<br>{@code T m(A*);}</td><td>{@code (T) C.m(arg*);}</td>
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     * </tr>
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     * <tr>
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     *     <td>{@link java.lang.invoke.MethodHandles.Lookup#findSpecial lookup.findSpecial(C.class,"m",MT,this.class)}</td>
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     *     <td>{@code T m(A*);}</td><td>{@code (T) super.m(arg*);}</td>
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     * </tr>
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     * <tr>
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     *     <td>{@link java.lang.invoke.MethodHandles.Lookup#findConstructor lookup.findConstructor(C.class,MT)}</td>
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     *     <td>{@code C(A*);}</td><td>{@code new C(arg*);}</td>
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     * </tr>
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     * <tr>
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     *     <td>{@link java.lang.invoke.MethodHandles.Lookup#unreflectGetter lookup.unreflectGetter(aField)}</td>
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     *     <td>({@code static})?<br>{@code FT f;}</td><td>{@code (FT) aField.get(thisOrNull);}</td>
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     * </tr>
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     * <tr>
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     *     <td>{@link java.lang.invoke.MethodHandles.Lookup#unreflectSetter lookup.unreflectSetter(aField)}</td>
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     *     <td>({@code static})?<br>{@code FT f;}</td><td>{@code aField.set(thisOrNull, arg);}</td>
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     * </tr>
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     * <tr>
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     *     <td>{@link java.lang.invoke.MethodHandles.Lookup#unreflect lookup.unreflect(aMethod)}</td>
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     *     <td>({@code static})?<br>{@code T m(A*);}</td><td>{@code (T) aMethod.invoke(thisOrNull, arg*);}</td>
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     * </tr>
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     * <tr>
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     *     <td>{@link java.lang.invoke.MethodHandles.Lookup#unreflectConstructor lookup.unreflectConstructor(aConstructor)}</td>
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     *     <td>{@code C(A*);}</td><td>{@code (C) aConstructor.newInstance(arg*);}</td>
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     * </tr>
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     * <tr>
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     *     <td>{@link java.lang.invoke.MethodHandles.Lookup#unreflect lookup.unreflect(aMethod)}</td>
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     *     <td>({@code static})?<br>{@code T m(A*);}</td><td>{@code (T) aMethod.invoke(thisOrNull, arg*);}</td>
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     * </tr>
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     * </table>
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     *
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     * Here, the type {@code C} is the class or interface being searched for a member,
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     * documented as a parameter named {@code refc} in the lookup methods.
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     * The method type {@code MT} is composed from the return type {@code T}
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     * and the sequence of argument types {@code A*}.
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     * The constructor also has a sequence of argument types {@code A*} and
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     * is deemed to return the newly-created object of type {@code C}.
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     * Both {@code MT} and the field type {@code FT} are documented as a parameter named {@code type}.
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     * The formal parameter {@code this} stands for the self-reference of type {@code C};
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     * if it is present, it is always the leading argument to the method handle invocation.
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     * (In the case of some {@code protected} members, {@code this} may be
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     * restricted in type to the lookup class; see below.)
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     * The name {@code arg} stands for all the other method handle arguments.
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     * In the code examples for the Core Reflection API, the name {@code thisOrNull}
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     * stands for a null reference if the accessed method or field is static,
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     * and {@code this} otherwise.
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     * The names {@code aMethod}, {@code aField}, and {@code aConstructor} stand
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     * for reflective objects corresponding to the given members.
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     * <p>
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     * In cases where the given member is of variable arity (i.e., a method or constructor)
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     * the returned method handle will also be of {@linkplain MethodHandle#asVarargsCollector variable arity}.
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     * In all other cases, the returned method handle will be of fixed arity.
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     * <p style="font-size:smaller;">
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     * <em>Discussion:</em>
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     * The equivalence between looked-up method handles and underlying
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     * class members and bytecode behaviors
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     * can break down in a few ways:
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     * <ul style="font-size:smaller;">
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     * <li>If {@code C} is not symbolically accessible from the lookup class's loader,
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     * the lookup can still succeed, even when there is no equivalent
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     * Java expression or bytecoded constant.
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     * <li>Likewise, if {@code T} or {@code MT}
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     * is not symbolically accessible from the lookup class's loader,
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     * the lookup can still succeed.
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     * For example, lookups for {@code MethodHandle.invokeExact} and
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     * {@code MethodHandle.invoke} will always succeed, regardless of requested type.
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     * <li>If there is a security manager installed, it can forbid the lookup
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     * on various grounds (<a href="MethodHandles.Lookup.html#secmgr">see below</a>).
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     * By contrast, the {@code ldc} instruction on a {@code CONSTANT_MethodHandle}
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     * constant is not subject to security manager checks.
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     * <li>If the looked-up method has a
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     * <a href="MethodHandle.html#maxarity">very large arity</a>,
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     * the method handle creation may fail, due to the method handle
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     * type having too many parameters.
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     * </ul>
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     *
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     * <h1><a name="access"></a>Access checking</h1>
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     * Access checks are applied in the factory methods of {@code Lookup},
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     * when a method handle is created.
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     * This is a key difference from the Core Reflection API, since
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     * {@link java.lang.reflect.Method#invoke java.lang.reflect.Method.invoke}
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     * performs access checking against every caller, on every call.
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     * <p>
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     * All access checks start from a {@code Lookup} object, which
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     * compares its recorded lookup class against all requests to
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     * create method handles.
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     * A single {@code Lookup} object can be used to create any number
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     * of access-checked method handles, all checked against a single
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     * lookup class.
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     * <p>
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     * A {@code Lookup} object can be shared with other trusted code,
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     * such as a metaobject protocol.
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     * A shared {@code Lookup} object delegates the capability
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     * to create method handles on private members of the lookup class.
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     * Even if privileged code uses the {@code Lookup} object,
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     * the access checking is confined to the privileges of the
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     * original lookup class.
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     * <p>
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     * A lookup can fail, because
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     * the containing class is not accessible to the lookup class, or
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     * because the desired class member is missing, or because the
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     * desired class member is not accessible to the lookup class, or
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     * because the lookup object is not trusted enough to access the member.
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     * In any of these cases, a {@code ReflectiveOperationException} will be
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     * thrown from the attempted lookup.  The exact class will be one of
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     * the following:
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     * <ul>
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     * <li>NoSuchMethodException &mdash; if a method is requested but does not exist
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     * <li>NoSuchFieldException &mdash; if a field is requested but does not exist
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     * <li>IllegalAccessException &mdash; if the member exists but an access check fails
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     * </ul>
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     * <p>
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     * In general, the conditions under which a method handle may be
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     * looked up for a method {@code M} are no more restrictive than the conditions
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     * under which the lookup class could have compiled, verified, and resolved a call to {@code M}.
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     * Where the JVM would raise exceptions like {@code NoSuchMethodError},
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     * a method handle lookup will generally raise a corresponding
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     * checked exception, such as {@code NoSuchMethodException}.
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     * And the effect of invoking the method handle resulting from the lookup
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     * is <a href="MethodHandles.Lookup.html#equiv">exactly equivalent</a>
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     * to executing the compiled, verified, and resolved call to {@code M}.
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     * The same point is true of fields and constructors.
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     * <p style="font-size:smaller;">
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     * <em>Discussion:</em>
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     * Access checks only apply to named and reflected methods,
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     * constructors, and fields.
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     * Other method handle creation methods, such as
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     * {@link MethodHandle#asType MethodHandle.asType},
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     * do not require any access checks, and are used
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     * independently of any {@code Lookup} object.
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     * <p>
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     * If the desired member is {@code protected}, the usual JVM rules apply,
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     * including the requirement that the lookup class must be either be in the
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     * same package as the desired member, or must inherit that member.
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     * (See the Java Virtual Machine Specification, sections 4.9.2, 5.4.3.5, and 6.4.)
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     * In addition, if the desired member is a non-static field or method
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     * in a different package, the resulting method handle may only be applied
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     * to objects of the lookup class or one of its subclasses.
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     * This requirement is enforced by narrowing the type of the leading
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     * {@code this} parameter from {@code C}
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     * (which will necessarily be a superclass of the lookup class)
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     * to the lookup class itself.
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     * <p>
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     * The JVM imposes a similar requirement on {@code invokespecial} instruction,
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     * that the receiver argument must match both the resolved method <em>and</em>
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     * the current class.  Again, this requirement is enforced by narrowing the
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     * type of the leading parameter to the resulting method handle.
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   353
     * (See the Java Virtual Machine Specification, section 4.10.1.9.)
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   354
     * <p>
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     * The JVM represents constructors and static initializer blocks as internal methods
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     * with special names ({@code "<init>"} and {@code "<clinit>"}).
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   357
     * The internal syntax of invocation instructions allows them to refer to such internal
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     * methods as if they were normal methods, but the JVM bytecode verifier rejects them.
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     * A lookup of such an internal method will produce a {@code NoSuchMethodException}.
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   360
     * <p>
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   361
     * In some cases, access between nested classes is obtained by the Java compiler by creating
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   362
     * an wrapper method to access a private method of another class
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   363
     * in the same top-level declaration.
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   364
     * For example, a nested class {@code C.D}
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   365
     * can access private members within other related classes such as
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   366
     * {@code C}, {@code C.D.E}, or {@code C.B},
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   367
     * but the Java compiler may need to generate wrapper methods in
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   368
     * those related classes.  In such cases, a {@code Lookup} object on
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   369
     * {@code C.E} would be unable to those private members.
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   370
     * A workaround for this limitation is the {@link Lookup#in Lookup.in} method,
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   371
     * which can transform a lookup on {@code C.E} into one on any of those other
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   372
     * classes, without special elevation of privilege.
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   373
     * <p>
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   374
     * The accesses permitted to a given lookup object may be limited,
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   375
     * according to its set of {@link #lookupModes lookupModes},
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   376
     * to a subset of members normally accessible to the lookup class.
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   377
     * For example, the {@link MethodHandles#publicLookup publicLookup}
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   378
     * method produces a lookup object which is only allowed to access
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   379
     * public members in public classes.
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   380
     * The caller sensitive method {@link MethodHandles#lookup lookup}
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   381
     * produces a lookup object with full capabilities relative to
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   382
     * its caller class, to emulate all supported bytecode behaviors.
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   383
     * Also, the {@link Lookup#in Lookup.in} method may produce a lookup object
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   384
     * with fewer access modes than the original lookup object.
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   385
     *
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   386
     * <p style="font-size:smaller;">
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   387
     * <a name="privacc"></a>
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   388
     * <em>Discussion of private access:</em>
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   389
     * We say that a lookup has <em>private access</em>
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   390
     * if its {@linkplain #lookupModes lookup modes}
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   391
     * include the possibility of accessing {@code private} members.
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   392
     * As documented in the relevant methods elsewhere,
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   393
     * only lookups with private access possess the following capabilities:
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   394
     * <ul style="font-size:smaller;">
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   395
     * <li>access private fields, methods, and constructors of the lookup class
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   396
     * <li>create method handles which invoke <a href="MethodHandles.Lookup.html#callsens">caller sensitive</a> methods,
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   397
     *     such as {@code Class.forName}
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   398
     * <li>create method handles which {@link Lookup#findSpecial emulate invokespecial} instructions
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   399
     * <li>avoid <a href="MethodHandles.Lookup.html#secmgr">package access checks</a>
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   400
     *     for classes accessible to the lookup class
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   401
     * <li>create {@link Lookup#in delegated lookup objects} which have private access to other classes
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   402
     *     within the same package member
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diff changeset
   403
     * </ul>
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   404
     * <p style="font-size:smaller;">
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   405
     * Each of these permissions is a consequence of the fact that a lookup object
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diff changeset
   406
     * with private access can be securely traced back to an originating class,
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diff changeset
   407
     * whose <a href="MethodHandles.Lookup.html#equiv">bytecode behaviors</a> and Java language access permissions
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diff changeset
   408
     * can be reliably determined and emulated by method handles.
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   409
     *
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diff changeset
   410
     * <h1><a name="secmgr"></a>Security manager interactions</h1>
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   411
     * Although bytecode instructions can only refer to classes in
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   412
     * a related class loader, this API can search for methods in any
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   413
     * class, as long as a reference to its {@code Class} object is
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   414
     * available.  Such cross-loader references are also possible with the
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   415
     * Core Reflection API, and are impossible to bytecode instructions
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   416
     * such as {@code invokestatic} or {@code getfield}.
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   417
     * There is a {@linkplain java.lang.SecurityManager security manager API}
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   418
     * to allow applications to check such cross-loader references.
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   419
     * These checks apply to both the {@code MethodHandles.Lookup} API
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   420
     * and the Core Reflection API
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   421
     * (as found on {@link java.lang.Class Class}).
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   422
     * <p>
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   423
     * If a security manager is present, member lookups are subject to
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   424
     * additional checks.
18766
28c62f5e9a47 8007035: deprecate public void SecurityManager.checkMemberAccess(Class<?> clazz, int which)
mchung
parents: 18569
diff changeset
   425
     * From one to three calls are made to the security manager.
8349
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   426
     * Any of these calls can refuse access by throwing a
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   427
     * {@link java.lang.SecurityException SecurityException}.
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   428
     * Define {@code smgr} as the security manager,
18766
28c62f5e9a47 8007035: deprecate public void SecurityManager.checkMemberAccess(Class<?> clazz, int which)
mchung
parents: 18569
diff changeset
   429
     * {@code lookc} as the lookup class of the current lookup object,
8349
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   430
     * {@code refc} as the containing class in which the member
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   431
     * is being sought, and {@code defc} as the class in which the
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   432
     * member is actually defined.
18766
28c62f5e9a47 8007035: deprecate public void SecurityManager.checkMemberAccess(Class<?> clazz, int which)
mchung
parents: 18569
diff changeset
   433
     * The value {@code lookc} is defined as <em>not present</em>
28c62f5e9a47 8007035: deprecate public void SecurityManager.checkMemberAccess(Class<?> clazz, int which)
mchung
parents: 18569
diff changeset
   434
     * if the current lookup object does not have
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   435
     * <a href="MethodHandles.Lookup.html#privacc">private access</a>.
8349
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   436
     * The calls are made according to the following rules:
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   437
     * <ul>
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
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parents: 20534
diff changeset
   438
     * <li><b>Step 1:</b>
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   439
     *     If {@code lookc} is not present, or if its class loader is not
8349
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   440
     *     the same as or an ancestor of the class loader of {@code refc},
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   441
     *     then {@link SecurityManager#checkPackageAccess
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   442
     *     smgr.checkPackageAccess(refcPkg)} is called,
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   443
     *     where {@code refcPkg} is the package of {@code refc}.
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   444
     * <li><b>Step 2:</b>
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   445
     *     If the retrieved member is not public and
18766
28c62f5e9a47 8007035: deprecate public void SecurityManager.checkMemberAccess(Class<?> clazz, int which)
mchung
parents: 18569
diff changeset
   446
     *     {@code lookc} is not present, then
28c62f5e9a47 8007035: deprecate public void SecurityManager.checkMemberAccess(Class<?> clazz, int which)
mchung
parents: 18569
diff changeset
   447
     *     {@link SecurityManager#checkPermission smgr.checkPermission}
28c62f5e9a47 8007035: deprecate public void SecurityManager.checkMemberAccess(Class<?> clazz, int which)
mchung
parents: 18569
diff changeset
   448
     *     with {@code RuntimePermission("accessDeclaredMembers")} is called.
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   449
     * <li><b>Step 3:</b>
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   450
     *     If the retrieved member is not public,
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   451
     *     and if {@code lookc} is not present,
18766
28c62f5e9a47 8007035: deprecate public void SecurityManager.checkMemberAccess(Class<?> clazz, int which)
mchung
parents: 18569
diff changeset
   452
     *     and if {@code defc} and {@code refc} are different,
8349
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   453
     *     then {@link SecurityManager#checkPackageAccess
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   454
     *     smgr.checkPackageAccess(defcPkg)} is called,
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   455
     *     where {@code defcPkg} is the package of {@code defc}.
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   456
     * </ul>
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   457
     * Security checks are performed after other access checks have passed.
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   458
     * Therefore, the above rules presuppose a member that is public,
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   459
     * or else that is being accessed from a lookup class that has
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   460
     * rights to access the member.
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   461
     *
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   462
     * <h1><a name="callsens"></a>Caller sensitive methods</h1>
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   463
     * A small number of Java methods have a special property called caller sensitivity.
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   464
     * A <em>caller-sensitive</em> method can behave differently depending on the
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   465
     * identity of its immediate caller.
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   466
     * <p>
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   467
     * If a method handle for a caller-sensitive method is requested,
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   468
     * the general rules for <a href="MethodHandles.Lookup.html#equiv">bytecode behaviors</a> apply,
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   469
     * but they take account of the lookup class in a special way.
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   470
     * The resulting method handle behaves as if it were called
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   471
     * from an instruction contained in the lookup class,
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   472
     * so that the caller-sensitive method detects the lookup class.
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   473
     * (By contrast, the invoker of the method handle is disregarded.)
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   474
     * Thus, in the case of caller-sensitive methods,
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   475
     * different lookup classes may give rise to
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   476
     * differently behaving method handles.
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   477
     * <p>
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   478
     * In cases where the lookup object is
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   479
     * {@link MethodHandles#publicLookup() publicLookup()},
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   480
     * or some other lookup object without
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   481
     * <a href="MethodHandles.Lookup.html#privacc">private access</a>,
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   482
     * the lookup class is disregarded.
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   483
     * In such cases, no caller-sensitive method handle can be created,
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   484
     * access is forbidden, and the lookup fails with an
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
   485
     * {@code IllegalAccessException}.
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   486
     * <p style="font-size:smaller;">
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   487
     * <em>Discussion:</em>
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   488
     * For example, the caller-sensitive method
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   489
     * {@link java.lang.Class#forName(String) Class.forName(x)}
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   490
     * can return varying classes or throw varying exceptions,
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   491
     * depending on the class loader of the class that calls it.
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   492
     * A public lookup of {@code Class.forName} will fail, because
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   493
     * there is no reasonable way to determine its bytecode behavior.
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   494
     * <p style="font-size:smaller;">
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   495
     * If an application caches method handles for broad sharing,
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   496
     * it should use {@code publicLookup()} to create them.
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   497
     * If there is a lookup of {@code Class.forName}, it will fail,
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   498
     * and the application must take appropriate action in that case.
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   499
     * It may be that a later lookup, perhaps during the invocation of a
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   500
     * bootstrap method, can incorporate the specific identity
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   501
     * of the caller, making the method accessible.
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   502
     * <p style="font-size:smaller;">
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   503
     * The function {@code MethodHandles.lookup} is caller sensitive
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   504
     * so that there can be a secure foundation for lookups.
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   505
     * Nearly all other methods in the JSR 292 API rely on lookup
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   506
     * objects to check access requests.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   507
     */
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   508
    public static final
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   509
    class Lookup {
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   510
        /** The class on behalf of whom the lookup is being performed. */
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   511
        private final Class<?> lookupClass;
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   512
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   513
        /** The allowed sorts of members which may be looked up (PUBLIC, etc.). */
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   514
        private final int allowedModes;
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   515
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   516
        /** A single-bit mask representing {@code public} access,
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   517
         *  which may contribute to the result of {@link #lookupModes lookupModes}.
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   518
         *  The value, {@code 0x01}, happens to be the same as the value of the
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   519
         *  {@code public} {@linkplain java.lang.reflect.Modifier#PUBLIC modifier bit}.
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   520
         */
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   521
        public static final int PUBLIC = Modifier.PUBLIC;
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   522
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   523
        /** A single-bit mask representing {@code private} access,
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   524
         *  which may contribute to the result of {@link #lookupModes lookupModes}.
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   525
         *  The value, {@code 0x02}, happens to be the same as the value of the
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   526
         *  {@code private} {@linkplain java.lang.reflect.Modifier#PRIVATE modifier bit}.
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   527
         */
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   528
        public static final int PRIVATE = Modifier.PRIVATE;
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   529
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   530
        /** A single-bit mask representing {@code protected} access,
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   531
         *  which may contribute to the result of {@link #lookupModes lookupModes}.
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   532
         *  The value, {@code 0x04}, happens to be the same as the value of the
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   533
         *  {@code protected} {@linkplain java.lang.reflect.Modifier#PROTECTED modifier bit}.
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   534
         */
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   535
        public static final int PROTECTED = Modifier.PROTECTED;
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   536
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   537
        /** A single-bit mask representing {@code package} access (default access),
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   538
         *  which may contribute to the result of {@link #lookupModes lookupModes}.
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   539
         *  The value is {@code 0x08}, which does not correspond meaningfully to
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   540
         *  any particular {@linkplain java.lang.reflect.Modifier modifier bit}.
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   541
         */
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   542
        public static final int PACKAGE = Modifier.STATIC;
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   543
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   544
        private static final int ALL_MODES = (PUBLIC | PRIVATE | PROTECTED | PACKAGE);
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   545
        private static final int TRUSTED   = -1;
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   546
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   547
        private static int fixmods(int mods) {
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   548
            mods &= (ALL_MODES - PACKAGE);
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   549
            return (mods != 0) ? mods : PACKAGE;
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   550
        }
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   551
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   552
        /** Tells which class is performing the lookup.  It is this class against
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   553
         *  which checks are performed for visibility and access permissions.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   554
         *  <p>
7052
963a5baf2ba3 6980096: JSR 292 reflective lookup should throw checked exceptions
jrose
parents: 5727
diff changeset
   555
         *  The class implies a maximum level of access permission,
963a5baf2ba3 6980096: JSR 292 reflective lookup should throw checked exceptions
jrose
parents: 5727
diff changeset
   556
         *  but the permissions may be additionally limited by the bitmask
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   557
         *  {@link #lookupModes lookupModes}, which controls whether non-public members
7052
963a5baf2ba3 6980096: JSR 292 reflective lookup should throw checked exceptions
jrose
parents: 5727
diff changeset
   558
         *  can be accessed.
18569
0e46c17766b7 8019357: Fix doclint warnings in java.lang.invoke
darcy
parents: 18274
diff changeset
   559
         *  @return the lookup class, on behalf of which this lookup object finds members
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   560
         */
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   561
        public Class<?> lookupClass() {
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   562
            return lookupClass;
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   563
        }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   564
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   565
        // This is just for calling out to MethodHandleImpl.
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   566
        private Class<?> lookupClassOrNull() {
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   567
            return (allowedModes == TRUSTED) ? null : lookupClass;
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   568
        }
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   569
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   570
        /** Tells which access-protection classes of members this lookup object can produce.
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   571
         *  The result is a bit-mask of the bits
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   572
         *  {@linkplain #PUBLIC PUBLIC (0x01)},
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   573
         *  {@linkplain #PRIVATE PRIVATE (0x02)},
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   574
         *  {@linkplain #PROTECTED PROTECTED (0x04)},
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   575
         *  and {@linkplain #PACKAGE PACKAGE (0x08)}.
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   576
         *  <p>
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   577
         *  A freshly-created lookup object
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
   578
         *  on the {@linkplain java.lang.invoke.MethodHandles#lookup() caller's class}
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   579
         *  has all possible bits set, since the caller class can access all its own members.
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   580
         *  A lookup object on a new lookup class
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
   581
         *  {@linkplain java.lang.invoke.MethodHandles.Lookup#in created from a previous lookup object}
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   582
         *  may have some mode bits set to zero.
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   583
         *  The purpose of this is to restrict access via the new lookup object,
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   584
         *  so that it can access only names which can be reached by the original
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   585
         *  lookup object, and also by the new lookup class.
18569
0e46c17766b7 8019357: Fix doclint warnings in java.lang.invoke
darcy
parents: 18274
diff changeset
   586
         *  @return the lookup modes, which limit the kinds of access performed by this lookup object
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   587
         */
7052
963a5baf2ba3 6980096: JSR 292 reflective lookup should throw checked exceptions
jrose
parents: 5727
diff changeset
   588
        public int lookupModes() {
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   589
            return allowedModes & ALL_MODES;
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   590
        }
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   591
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   592
        /** Embody the current class (the lookupClass) as a lookup class
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   593
         * for method handle creation.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   594
         * Must be called by from a method in this package,
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   595
         * which in turn is called by a method not in this package.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   596
         */
16906
44dfee24cb71 8010117: Annotate jdk caller sensitive methods with @sun.reflect.CallerSensitive
mchung
parents: 16898
diff changeset
   597
        Lookup(Class<?> lookupClass) {
44dfee24cb71 8010117: Annotate jdk caller sensitive methods with @sun.reflect.CallerSensitive
mchung
parents: 16898
diff changeset
   598
            this(lookupClass, ALL_MODES);
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   599
            // make sure we haven't accidentally picked up a privileged class:
20825
3d5429b4b601 8017196: Ensure Proxies are handled appropriately
mchung
parents: 18569
diff changeset
   600
            checkUnprivilegedlookupClass(lookupClass, ALL_MODES);
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
   601
        }
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
   602
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   603
        private Lookup(Class<?> lookupClass, int allowedModes) {
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
   604
            this.lookupClass = lookupClass;
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   605
            this.allowedModes = allowedModes;
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
   606
        }
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
   607
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
   608
        /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   609
         * Creates a lookup on the specified new lookup class.
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   610
         * The resulting object will report the specified
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   611
         * class as its own {@link #lookupClass lookupClass}.
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   612
         * <p>
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   613
         * However, the resulting {@code Lookup} object is guaranteed
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   614
         * to have no more access capabilities than the original.
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   615
         * In particular, access capabilities can be lost as follows:<ul>
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   616
         * <li>If the new lookup class differs from the old one,
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   617
         * protected members will not be accessible by virtue of inheritance.
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   618
         * (Protected members may continue to be accessible because of package sharing.)
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   619
         * <li>If the new lookup class is in a different package
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   620
         * than the old one, protected and default (package) members will not be accessible.
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   621
         * <li>If the new lookup class is not within the same package member
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   622
         * as the old one, private members will not be accessible.
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   623
         * <li>If the new lookup class is not accessible to the old lookup class,
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   624
         * then no members, not even public members, will be accessible.
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   625
         * (In all other cases, public members will continue to be accessible.)
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   626
         * </ul>
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   627
         *
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   628
         * @param requestedLookupClass the desired lookup class for the new lookup object
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   629
         * @return a lookup object which reports the desired lookup class
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   630
         * @throws NullPointerException if the argument is null
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
   631
         */
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   632
        public Lookup in(Class<?> requestedLookupClass) {
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   633
            requestedLookupClass.getClass();  // null check
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   634
            if (allowedModes == TRUSTED)  // IMPL_LOOKUP can make any lookup at all
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   635
                return new Lookup(requestedLookupClass, ALL_MODES);
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   636
            if (requestedLookupClass == this.lookupClass)
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   637
                return this;  // keep same capabilities
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   638
            int newModes = (allowedModes & (ALL_MODES & ~PROTECTED));
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   639
            if ((newModes & PACKAGE) != 0
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   640
                && !VerifyAccess.isSamePackage(this.lookupClass, requestedLookupClass)) {
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   641
                newModes &= ~(PACKAGE|PRIVATE);
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
   642
            }
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   643
            // Allow nestmate lookups to be created without special privilege:
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   644
            if ((newModes & PRIVATE) != 0
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   645
                && !VerifyAccess.isSamePackageMember(this.lookupClass, requestedLookupClass)) {
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   646
                newModes &= ~PRIVATE;
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   647
            }
13044
8411854afc2b 7165628: Issues with java.lang.invoke.MethodHandles.Lookup
jrose
parents: 11535
diff changeset
   648
            if ((newModes & PUBLIC) != 0
8411854afc2b 7165628: Issues with java.lang.invoke.MethodHandles.Lookup
jrose
parents: 11535
diff changeset
   649
                && !VerifyAccess.isClassAccessible(requestedLookupClass, this.lookupClass, allowedModes)) {
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   650
                // The requested class it not accessible from the lookup class.
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   651
                // No permissions.
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   652
                newModes = 0;
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   653
            }
20825
3d5429b4b601 8017196: Ensure Proxies are handled appropriately
mchung
parents: 18569
diff changeset
   654
            checkUnprivilegedlookupClass(requestedLookupClass, newModes);
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   655
            return new Lookup(requestedLookupClass, newModes);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   656
        }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   657
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
   658
        // Make sure outer class is initialized first.
8821
2836ee97ee27 6839872: remove implementation inheritance from JSR 292 APIs
jrose
parents: 8349
diff changeset
   659
        static { IMPL_NAMES.getClass(); }
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
   660
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   661
        /** Version of lookup which is trusted minimally.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   662
         *  It can only be used to create method handles to
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   663
         *  publicly accessible members.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   664
         */
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   665
        static final Lookup PUBLIC_LOOKUP = new Lookup(Object.class, PUBLIC);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   666
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   667
        /** Package-private version of lookup which is trusted. */
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   668
        static final Lookup IMPL_LOOKUP = new Lookup(Object.class, TRUSTED);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   669
20825
3d5429b4b601 8017196: Ensure Proxies are handled appropriately
mchung
parents: 18569
diff changeset
   670
        private static void checkUnprivilegedlookupClass(Class<?> lookupClass, int allowedModes) {
2764
2e45af54c0f9 6839839: access checking logic is wrong at three points in MethodHandles
jrose
parents: 2763
diff changeset
   671
            String name = lookupClass.getName();
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
   672
            if (name.startsWith("java.lang.invoke."))
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   673
                throw newIllegalArgumentException("illegal lookupClass: "+lookupClass);
20825
3d5429b4b601 8017196: Ensure Proxies are handled appropriately
mchung
parents: 18569
diff changeset
   674
3d5429b4b601 8017196: Ensure Proxies are handled appropriately
mchung
parents: 18569
diff changeset
   675
            // For caller-sensitive MethodHandles.lookup()
3d5429b4b601 8017196: Ensure Proxies are handled appropriately
mchung
parents: 18569
diff changeset
   676
            // disallow lookup more restricted packages
3d5429b4b601 8017196: Ensure Proxies are handled appropriately
mchung
parents: 18569
diff changeset
   677
            if (allowedModes == ALL_MODES && lookupClass.getClassLoader() == null) {
3d5429b4b601 8017196: Ensure Proxies are handled appropriately
mchung
parents: 18569
diff changeset
   678
                if (name.startsWith("java.") ||
3d5429b4b601 8017196: Ensure Proxies are handled appropriately
mchung
parents: 18569
diff changeset
   679
                        (name.startsWith("sun.") && !name.startsWith("sun.invoke."))) {
3d5429b4b601 8017196: Ensure Proxies are handled appropriately
mchung
parents: 18569
diff changeset
   680
                    throw newIllegalArgumentException("illegal lookupClass: " + lookupClass);
3d5429b4b601 8017196: Ensure Proxies are handled appropriately
mchung
parents: 18569
diff changeset
   681
                }
3d5429b4b601 8017196: Ensure Proxies are handled appropriately
mchung
parents: 18569
diff changeset
   682
            }
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   683
        }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   684
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   685
        /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   686
         * Displays the name of the class from which lookups are to be made.
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   687
         * (The name is the one reported by {@link java.lang.Class#getName() Class.getName}.)
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   688
         * If there are restrictions on the access permitted to this lookup,
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   689
         * this is indicated by adding a suffix to the class name, consisting
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   690
         * of a slash and a keyword.  The keyword represents the strongest
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   691
         * allowed access, and is chosen as follows:
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   692
         * <ul>
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   693
         * <li>If no access is allowed, the suffix is "/noaccess".
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   694
         * <li>If only public access is allowed, the suffix is "/public".
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   695
         * <li>If only public and package access are allowed, the suffix is "/package".
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   696
         * <li>If only public, package, and private access are allowed, the suffix is "/private".
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   697
         * </ul>
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   698
         * If none of the above cases apply, it is the case that full
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   699
         * access (public, package, private, and protected) is allowed.
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   700
         * In this case, no suffix is added.
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   701
         * This is true only of an object obtained originally from
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
   702
         * {@link java.lang.invoke.MethodHandles#lookup MethodHandles.lookup}.
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
   703
         * Objects created by {@link java.lang.invoke.MethodHandles.Lookup#in Lookup.in}
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   704
         * always have restricted access, and will display a suffix.
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   705
         * <p>
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   706
         * (It may seem strange that protected access should be
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   707
         * stronger than private access.  Viewed independently from
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   708
         * package access, protected access is the first to be lost,
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   709
         * because it requires a direct subclass relationship between
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   710
         * caller and callee.)
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   711
         * @see #in
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   712
         */
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   713
        @Override
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   714
        public String toString() {
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   715
            String cname = lookupClass.getName();
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   716
            switch (allowedModes) {
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   717
            case 0:  // no privileges
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   718
                return cname + "/noaccess";
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   719
            case PUBLIC:
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
   720
                return cname + "/public";
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   721
            case PUBLIC|PACKAGE:
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   722
                return cname + "/package";
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   723
            case ALL_MODES & ~PROTECTED:
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   724
                return cname + "/private";
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   725
            case ALL_MODES:
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   726
                return cname;
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   727
            case TRUSTED:
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   728
                return "/trusted";  // internal only; not exported
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   729
            default:  // Should not happen, but it's a bitfield...
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   730
                cname = cname + "/" + Integer.toHexString(allowedModes);
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   731
                assert(false) : cname;
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   732
                return cname;
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   733
            }
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   734
        }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   735
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   736
        /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   737
         * Produces a method handle for a static method.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   738
         * The type of the method handle will be that of the method.
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
   739
         * (Since static methods do not take receivers, there is no
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
   740
         * additional receiver argument inserted into the method handle type,
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   741
         * as there would be with {@link #findVirtual findVirtual} or {@link #findSpecial findSpecial}.)
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   742
         * The method and all its argument types must be accessible to the lookup object.
8345
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
   743
         * <p>
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
   744
         * The returned method handle will have
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
   745
         * {@linkplain MethodHandle#asVarargsCollector variable arity} if and only if
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
   746
         * the method's variable arity modifier bit ({@code 0x0080}) is set.
20532
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
   747
         * <p>
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
   748
         * If the returned method handle is invoked, the method's class will
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
   749
         * be initialized, if it has not already been initialized.
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
   750
         * <p><b>Example:</b>
20877
83ea903d5cf1 8026183: minor documentation problems in java.lang.invoke
rriggs
parents: 20853
diff changeset
   751
         * <blockquote><pre>{@code
20531
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   752
import static java.lang.invoke.MethodHandles.*;
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   753
import static java.lang.invoke.MethodType.*;
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   754
...
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   755
MethodHandle MH_asList = publicLookup().findStatic(Arrays.class,
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   756
  "asList", methodType(List.class, Object[].class));
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   757
assertEquals("[x, y]", MH_asList.invoke("x", "y").toString());
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   758
         * }</pre></blockquote>
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   759
         * @param refc the class from which the method is accessed
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   760
         * @param name the name of the method
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   761
         * @param type the type of the method
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   762
         * @return the desired method handle
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
   763
         * @throws NoSuchMethodException if the method does not exist
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
   764
         * @throws IllegalAccessException if access checking fails,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
   765
         *                                or if the method is not {@code static},
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
   766
         *                                or if the method's variable arity modifier bit
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
   767
         *                                is set and {@code asVarargsCollector} fails
8349
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   768
         * @exception SecurityException if a security manager is present and it
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   769
         *                              <a href="MethodHandles.Lookup.html#secmgr">refuses access</a>
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
   770
         * @throws NullPointerException if any argument is null
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   771
         */
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   772
        public
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
   773
        MethodHandle findStatic(Class<?> refc, String name, MethodType type) throws NoSuchMethodException, IllegalAccessException {
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   774
            MemberName method = resolveOrFail(REF_invokeStatic, refc, name, type);
18264
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
   775
            return getDirectMethod(REF_invokeStatic, refc, method, findBoundCallerClass(method));
9780
6fc3b49cfee4 7050328: (jsr-292) findConstructor throws ExceptionInInitializerError if run under SecurityManager
jrose
parents: 9752
diff changeset
   776
        }
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   777
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   778
        /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   779
         * Produces a method handle for a virtual method.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   780
         * The type of the method handle will be that of the method,
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   781
         * with the receiver type (usually {@code refc}) prepended.
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   782
         * The method and all its argument types must be accessible to the lookup object.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   783
         * <p>
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   784
         * When called, the handle will treat the first argument as a receiver
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   785
         * and dispatch on the receiver's type to determine which method
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   786
         * implementation to enter.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   787
         * (The dispatching action is identical with that performed by an
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   788
         * {@code invokevirtual} or {@code invokeinterface} instruction.)
8345
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
   789
         * <p>
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   790
         * The first argument will be of type {@code refc} if the lookup
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   791
         * class has full privileges to access the member.  Otherwise
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   792
         * the member must be {@code protected} and the first argument
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   793
         * will be restricted in type to the lookup class.
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   794
         * <p>
8345
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
   795
         * The returned method handle will have
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
   796
         * {@linkplain MethodHandle#asVarargsCollector variable arity} if and only if
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
   797
         * the method's variable arity modifier bit ({@code 0x0080}) is set.
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   798
         * <p>
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   799
         * Because of the general <a href="MethodHandles.Lookup.html#equiv">equivalence</a> between {@code invokevirtual}
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   800
         * instructions and method handles produced by {@code findVirtual},
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   801
         * if the class is {@code MethodHandle} and the name string is
9645
dabb5e4edc4c 7034977: JSR 292 MethodHandle.invokeGeneric should be renamed MethodHandle.invoke
jrose
parents: 8822
diff changeset
   802
         * {@code invokeExact} or {@code invoke}, the resulting
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   803
         * method handle is equivalent to one produced by
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
   804
         * {@link java.lang.invoke.MethodHandles#exactInvoker MethodHandles.exactInvoker} or
9645
dabb5e4edc4c 7034977: JSR 292 MethodHandle.invokeGeneric should be renamed MethodHandle.invoke
jrose
parents: 8822
diff changeset
   805
         * {@link java.lang.invoke.MethodHandles#invoker MethodHandles.invoker}
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   806
         * with the same {@code type} argument.
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   807
         *
20531
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   808
         * <b>Example:</b>
20877
83ea903d5cf1 8026183: minor documentation problems in java.lang.invoke
rriggs
parents: 20853
diff changeset
   809
         * <blockquote><pre>{@code
20531
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   810
import static java.lang.invoke.MethodHandles.*;
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   811
import static java.lang.invoke.MethodType.*;
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   812
...
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   813
MethodHandle MH_concat = publicLookup().findVirtual(String.class,
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   814
  "concat", methodType(String.class, String.class));
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   815
MethodHandle MH_hashCode = publicLookup().findVirtual(Object.class,
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   816
  "hashCode", methodType(int.class));
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   817
MethodHandle MH_hashCode_String = publicLookup().findVirtual(String.class,
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   818
  "hashCode", methodType(int.class));
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   819
assertEquals("xy", (String) MH_concat.invokeExact("x", "y"));
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   820
assertEquals("xy".hashCode(), (int) MH_hashCode.invokeExact((Object)"xy"));
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   821
assertEquals("xy".hashCode(), (int) MH_hashCode_String.invokeExact("xy"));
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   822
// interface method:
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   823
MethodHandle MH_subSequence = publicLookup().findVirtual(CharSequence.class,
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   824
  "subSequence", methodType(CharSequence.class, int.class, int.class));
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   825
assertEquals("def", MH_subSequence.invoke("abcdefghi", 3, 6).toString());
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   826
// constructor "internal method" must be accessed differently:
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   827
MethodType MT_newString = methodType(void.class); //()V for new String()
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   828
try { assertEquals("impossible", lookup()
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   829
        .findVirtual(String.class, "<init>", MT_newString));
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   830
 } catch (NoSuchMethodException ex) { } // OK
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   831
MethodHandle MH_newString = publicLookup()
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   832
  .findConstructor(String.class, MT_newString);
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   833
assertEquals("", (String) MH_newString.invokeExact());
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   834
         * }</pre></blockquote>
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   835
         *
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   836
         * @param refc the class or interface from which the method is accessed
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   837
         * @param name the name of the method
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   838
         * @param type the type of the method, with the receiver argument omitted
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   839
         * @return the desired method handle
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
   840
         * @throws NoSuchMethodException if the method does not exist
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
   841
         * @throws IllegalAccessException if access checking fails,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
   842
         *                                or if the method is {@code static}
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
   843
         *                                or if the method's variable arity modifier bit
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
   844
         *                                is set and {@code asVarargsCollector} fails
8349
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   845
         * @exception SecurityException if a security manager is present and it
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   846
         *                              <a href="MethodHandles.Lookup.html#secmgr">refuses access</a>
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
   847
         * @throws NullPointerException if any argument is null
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   848
         */
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
   849
        public MethodHandle findVirtual(Class<?> refc, String name, MethodType type) throws NoSuchMethodException, IllegalAccessException {
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   850
            if (refc == MethodHandle.class) {
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   851
                MethodHandle mh = findVirtualForMH(name, type);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   852
                if (mh != null)  return mh;
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   853
            }
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   854
            byte refKind = (refc.isInterface() ? REF_invokeInterface : REF_invokeVirtual);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   855
            MemberName method = resolveOrFail(refKind, refc, name, type);
18264
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
   856
            return getDirectMethod(refKind, refc, method, findBoundCallerClass(method));
9780
6fc3b49cfee4 7050328: (jsr-292) findConstructor throws ExceptionInInitializerError if run under SecurityManager
jrose
parents: 9752
diff changeset
   857
        }
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   858
        private MethodHandle findVirtualForMH(String name, MethodType type) {
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   859
            // these names require special lookups because of the implicit MethodType argument
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   860
            if ("invoke".equals(name))
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   861
                return invoker(type);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   862
            if ("invokeExact".equals(name))
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   863
                return exactInvoker(type);
19804
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
   864
            assert(!MemberName.isMethodHandleInvokeName(name));
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   865
            return null;
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   866
        }
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   867
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   868
        /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
   869
         * Produces a method handle which creates an object and initializes it, using
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   870
         * the constructor of the specified type.
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   871
         * The parameter types of the method handle will be those of the constructor,
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   872
         * while the return type will be a reference to the constructor's class.
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   873
         * The constructor and all its argument types must be accessible to the lookup object.
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   874
         * <p>
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   875
         * The requested type must have a return type of {@code void}.
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   876
         * (This is consistent with the JVM's treatment of constructor type descriptors.)
8345
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
   877
         * <p>
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
   878
         * The returned method handle will have
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
   879
         * {@linkplain MethodHandle#asVarargsCollector variable arity} if and only if
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
   880
         * the constructor's variable arity modifier bit ({@code 0x0080}) is set.
20532
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
   881
         * <p>
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
   882
         * If the returned method handle is invoked, the constructor's class will
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
   883
         * be initialized, if it has not already been initialized.
20531
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   884
         * <p><b>Example:</b>
20877
83ea903d5cf1 8026183: minor documentation problems in java.lang.invoke
rriggs
parents: 20853
diff changeset
   885
         * <blockquote><pre>{@code
20531
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   886
import static java.lang.invoke.MethodHandles.*;
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   887
import static java.lang.invoke.MethodType.*;
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   888
...
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   889
MethodHandle MH_newArrayList = publicLookup().findConstructor(
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   890
  ArrayList.class, methodType(void.class, Collection.class));
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   891
Collection orig = Arrays.asList("x", "y");
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   892
Collection copy = (ArrayList) MH_newArrayList.invokeExact(orig);
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   893
assert(orig != copy);
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   894
assertEquals(orig, copy);
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   895
// a variable-arity constructor:
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   896
MethodHandle MH_newProcessBuilder = publicLookup().findConstructor(
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   897
  ProcessBuilder.class, methodType(void.class, String[].class));
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   898
ProcessBuilder pb = (ProcessBuilder)
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   899
  MH_newProcessBuilder.invoke("x", "y", "z");
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   900
assertEquals("[x, y, z]", pb.command().toString());
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   901
         * }</pre></blockquote>
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   902
         * @param refc the class or interface from which the method is accessed
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   903
         * @param type the type of the method, with the receiver argument omitted, and a void return type
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   904
         * @return the desired method handle
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
   905
         * @throws NoSuchMethodException if the constructor does not exist
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
   906
         * @throws IllegalAccessException if access checking fails
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
   907
         *                                or if the method's variable arity modifier bit
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
   908
         *                                is set and {@code asVarargsCollector} fails
8349
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   909
         * @exception SecurityException if a security manager is present and it
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   910
         *                              <a href="MethodHandles.Lookup.html#secmgr">refuses access</a>
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
   911
         * @throws NullPointerException if any argument is null
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   912
         */
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
   913
        public MethodHandle findConstructor(Class<?> refc, MethodType type) throws NoSuchMethodException, IllegalAccessException {
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   914
            String name = "<init>";
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   915
            MemberName ctor = resolveOrFail(REF_newInvokeSpecial, refc, name, type);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   916
            return getDirectConstructor(refc, ctor);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   917
        }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   918
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   919
        /**
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   920
         * Produces an early-bound method handle for a virtual method.
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   921
         * It will bypass checks for overriding methods on the receiver,
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   922
         * <a href="MethodHandles.Lookup.html#equiv">as if called</a> from an {@code invokespecial}
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   923
         * instruction from within the explicitly specified {@code specialCaller}.
2763
172d44ffd1e5 6839802: java.dyn needs to be on the CORE_PKGS list
jrose
parents: 2707
diff changeset
   924
         * The type of the method handle will be that of the method,
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   925
         * with a suitably restricted receiver type prepended.
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   926
         * (The receiver type will be {@code specialCaller} or a subtype.)
2763
172d44ffd1e5 6839802: java.dyn needs to be on the CORE_PKGS list
jrose
parents: 2707
diff changeset
   927
         * The method and all its argument types must be accessible
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   928
         * to the lookup object.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   929
         * <p>
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   930
         * Before method resolution,
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   931
         * if the explicitly specified caller class is not identical with the
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   932
         * lookup class, or if this lookup object does not have
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   933
         * <a href="MethodHandles.Lookup.html#privacc">private access</a>
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
   934
         * privileges, the access fails.
8345
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
   935
         * <p>
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
   936
         * The returned method handle will have
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
   937
         * {@linkplain MethodHandle#asVarargsCollector variable arity} if and only if
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
   938
         * the method's variable arity modifier bit ({@code 0x0080}) is set.
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
   939
         * <p style="font-size:smaller;">
20531
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   940
         * <em>(Note:  JVM internal methods named {@code "<init>"} are not visible to this API,
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   941
         * even though the {@code invokespecial} instruction can refer to them
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   942
         * in special circumstances.  Use {@link #findConstructor findConstructor}
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   943
         * to access instance initialization methods in a safe manner.)</em>
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   944
         * <p><b>Example:</b>
20877
83ea903d5cf1 8026183: minor documentation problems in java.lang.invoke
rriggs
parents: 20853
diff changeset
   945
         * <blockquote><pre>{@code
20531
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   946
import static java.lang.invoke.MethodHandles.*;
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   947
import static java.lang.invoke.MethodType.*;
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   948
...
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   949
static class Listie extends ArrayList {
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   950
  public String toString() { return "[wee Listie]"; }
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   951
  static Lookup lookup() { return MethodHandles.lookup(); }
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   952
}
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   953
...
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   954
// no access to constructor via invokeSpecial:
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   955
MethodHandle MH_newListie = Listie.lookup()
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   956
  .findConstructor(Listie.class, methodType(void.class));
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   957
Listie l = (Listie) MH_newListie.invokeExact();
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   958
try { assertEquals("impossible", Listie.lookup().findSpecial(
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   959
        Listie.class, "<init>", methodType(void.class), Listie.class));
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   960
 } catch (NoSuchMethodException ex) { } // OK
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   961
// access to super and self methods via invokeSpecial:
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   962
MethodHandle MH_super = Listie.lookup().findSpecial(
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   963
  ArrayList.class, "toString" , methodType(String.class), Listie.class);
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   964
MethodHandle MH_this = Listie.lookup().findSpecial(
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   965
  Listie.class, "toString" , methodType(String.class), Listie.class);
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   966
MethodHandle MH_duper = Listie.lookup().findSpecial(
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   967
  Object.class, "toString" , methodType(String.class), Listie.class);
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   968
assertEquals("[]", (String) MH_super.invokeExact(l));
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   969
assertEquals(""+l, (String) MH_this.invokeExact(l));
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   970
assertEquals("[]", (String) MH_duper.invokeExact(l)); // ArrayList method
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   971
try { assertEquals("inaccessible", Listie.lookup().findSpecial(
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   972
        String.class, "toString", methodType(String.class), Listie.class));
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   973
 } catch (IllegalAccessException ex) { } // OK
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   974
Listie subl = new Listie() { public String toString() { return "[subclass]"; } };
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   975
assertEquals(""+l, (String) MH_this.invokeExact(subl)); // Listie method
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   976
         * }</pre></blockquote>
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
   977
         *
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   978
         * @param refc the class or interface from which the method is accessed
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   979
         * @param name the name of the method (which must not be "&lt;init&gt;")
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   980
         * @param type the type of the method, with the receiver argument omitted
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   981
         * @param specialCaller the proposed calling class to perform the {@code invokespecial}
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   982
         * @return the desired method handle
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
   983
         * @throws NoSuchMethodException if the method does not exist
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
   984
         * @throws IllegalAccessException if access checking fails
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
   985
         *                                or if the method's variable arity modifier bit
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
   986
         *                                is set and {@code asVarargsCollector} fails
8349
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   987
         * @exception SecurityException if a security manager is present and it
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
   988
         *                              <a href="MethodHandles.Lookup.html#secmgr">refuses access</a>
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
   989
         * @throws NullPointerException if any argument is null
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
   990
         */
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   991
        public MethodHandle findSpecial(Class<?> refc, String name, MethodType type,
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
   992
                                        Class<?> specialCaller) throws NoSuchMethodException, IllegalAccessException {
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   993
            checkSpecialCaller(specialCaller);
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   994
            Lookup specialLookup = this.in(specialCaller);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
   995
            MemberName method = specialLookup.resolveOrFail(REF_invokeSpecial, refc, name, type);
18264
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
   996
            return specialLookup.getDirectMethod(REF_invokeSpecial, refc, method, findBoundCallerClass(method));
9780
6fc3b49cfee4 7050328: (jsr-292) findConstructor throws ExceptionInInitializerError if run under SecurityManager
jrose
parents: 9752
diff changeset
   997
        }
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   998
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
   999
        /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1000
         * Produces a method handle giving read access to a non-static field.
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1001
         * The type of the method handle will have a return type of the field's
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1002
         * value type.
5726
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1003
         * The method handle's single argument will be the instance containing
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1004
         * the field.
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1005
         * Access checking is performed immediately on behalf of the lookup class.
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1006
         * @param refc the class or interface from which the method is accessed
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1007
         * @param name the field's name
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1008
         * @param type the field's type
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1009
         * @return a method handle which can load values from the field
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1010
         * @throws NoSuchFieldException if the field does not exist
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1011
         * @throws IllegalAccessException if access checking fails, or if the field is {@code static}
8349
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
  1012
         * @exception SecurityException if a security manager is present and it
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
  1013
         *                              <a href="MethodHandles.Lookup.html#secmgr">refuses access</a>
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1014
         * @throws NullPointerException if any argument is null
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1015
         */
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1016
        public MethodHandle findGetter(Class<?> refc, String name, Class<?> type) throws NoSuchFieldException, IllegalAccessException {
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1017
            MemberName field = resolveOrFail(REF_getField, refc, name, type);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1018
            return getDirectField(REF_getField, refc, field);
9780
6fc3b49cfee4 7050328: (jsr-292) findConstructor throws ExceptionInInitializerError if run under SecurityManager
jrose
parents: 9752
diff changeset
  1019
        }
5726
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1020
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1021
        /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1022
         * Produces a method handle giving write access to a non-static field.
5726
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1023
         * The type of the method handle will have a void return type.
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1024
         * The method handle will take two arguments, the instance containing
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1025
         * the field, and the value to be stored.
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1026
         * The second argument will be of the field's value type.
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1027
         * Access checking is performed immediately on behalf of the lookup class.
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1028
         * @param refc the class or interface from which the method is accessed
5726
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1029
         * @param name the field's name
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1030
         * @param type the field's type
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1031
         * @return a method handle which can store values into the field
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1032
         * @throws NoSuchFieldException if the field does not exist
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1033
         * @throws IllegalAccessException if access checking fails, or if the field is {@code static}
8349
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
  1034
         * @exception SecurityException if a security manager is present and it
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
  1035
         *                              <a href="MethodHandles.Lookup.html#secmgr">refuses access</a>
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1036
         * @throws NullPointerException if any argument is null
5726
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1037
         */
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1038
        public MethodHandle findSetter(Class<?> refc, String name, Class<?> type) throws NoSuchFieldException, IllegalAccessException {
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1039
            MemberName field = resolveOrFail(REF_putField, refc, name, type);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1040
            return getDirectField(REF_putField, refc, field);
9780
6fc3b49cfee4 7050328: (jsr-292) findConstructor throws ExceptionInInitializerError if run under SecurityManager
jrose
parents: 9752
diff changeset
  1041
        }
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1042
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1043
        /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1044
         * Produces a method handle giving read access to a static field.
5726
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1045
         * The type of the method handle will have a return type of the field's
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1046
         * value type.
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1047
         * The method handle will take no arguments.
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1048
         * Access checking is performed immediately on behalf of the lookup class.
20532
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1049
         * <p>
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1050
         * If the returned method handle is invoked, the field's class will
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1051
         * be initialized, if it has not already been initialized.
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1052
         * @param refc the class or interface from which the method is accessed
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1053
         * @param name the field's name
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1054
         * @param type the field's type
5726
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1055
         * @return a method handle which can load values from the field
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1056
         * @throws NoSuchFieldException if the field does not exist
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1057
         * @throws IllegalAccessException if access checking fails, or if the field is not {@code static}
8349
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
  1058
         * @exception SecurityException if a security manager is present and it
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
  1059
         *                              <a href="MethodHandles.Lookup.html#secmgr">refuses access</a>
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1060
         * @throws NullPointerException if any argument is null
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1061
         */
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1062
        public MethodHandle findStaticGetter(Class<?> refc, String name, Class<?> type) throws NoSuchFieldException, IllegalAccessException {
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1063
            MemberName field = resolveOrFail(REF_getStatic, refc, name, type);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1064
            return getDirectField(REF_getStatic, refc, field);
9780
6fc3b49cfee4 7050328: (jsr-292) findConstructor throws ExceptionInInitializerError if run under SecurityManager
jrose
parents: 9752
diff changeset
  1065
        }
5726
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1066
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1067
        /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1068
         * Produces a method handle giving write access to a static field.
5726
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1069
         * The type of the method handle will have a void return type.
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1070
         * The method handle will take a single
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1071
         * argument, of the field's value type, the value to be stored.
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1072
         * Access checking is performed immediately on behalf of the lookup class.
20532
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1073
         * <p>
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1074
         * If the returned method handle is invoked, the field's class will
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1075
         * be initialized, if it has not already been initialized.
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1076
         * @param refc the class or interface from which the method is accessed
5726
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1077
         * @param name the field's name
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1078
         * @param type the field's type
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1079
         * @return a method handle which can store values into the field
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1080
         * @throws NoSuchFieldException if the field does not exist
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1081
         * @throws IllegalAccessException if access checking fails, or if the field is not {@code static}
8349
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
  1082
         * @exception SecurityException if a security manager is present and it
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
  1083
         *                              <a href="MethodHandles.Lookup.html#secmgr">refuses access</a>
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1084
         * @throws NullPointerException if any argument is null
5726
72c9d793224b 6939203: JSR 292 needs method handle constants
jrose
parents: 5722
diff changeset
  1085
         */
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1086
        public MethodHandle findStaticSetter(Class<?> refc, String name, Class<?> type) throws NoSuchFieldException, IllegalAccessException {
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1087
            MemberName field = resolveOrFail(REF_putStatic, refc, name, type);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1088
            return getDirectField(REF_putStatic, refc, field);
9780
6fc3b49cfee4 7050328: (jsr-292) findConstructor throws ExceptionInInitializerError if run under SecurityManager
jrose
parents: 9752
diff changeset
  1089
        }
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1090
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1091
        /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1092
         * Produces an early-bound method handle for a non-static method.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1093
         * The receiver must have a supertype {@code defc} in which a method
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1094
         * of the given name and type is accessible to the lookup class.
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1095
         * The method and all its argument types must be accessible to the lookup object.
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1096
         * The type of the method handle will be that of the method,
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1097
         * without any insertion of an additional receiver parameter.
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1098
         * The given receiver will be bound into the method handle,
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1099
         * so that every call to the method handle will invoke the
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1100
         * requested method on the given receiver.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1101
         * <p>
8345
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1102
         * The returned method handle will have
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1103
         * {@linkplain MethodHandle#asVarargsCollector variable arity} if and only if
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1104
         * the method's variable arity modifier bit ({@code 0x0080}) is set
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1105
         * <em>and</em> the trailing array argument is not the only argument.
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1106
         * (If the trailing array argument is the only argument,
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1107
         * the given receiver value will be bound to it.)
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1108
         * <p>
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1109
         * This is equivalent to the following code:
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1110
         * <blockquote><pre>{@code
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1111
import static java.lang.invoke.MethodHandles.*;
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1112
import static java.lang.invoke.MethodType.*;
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1113
...
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1114
MethodHandle mh0 = lookup().findVirtual(defc, name, type);
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1115
MethodHandle mh1 = mh0.bindTo(receiver);
8345
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1116
MethodType mt1 = mh1.type();
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1117
if (mh0.isVarargsCollector())
8345
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1118
  mh1 = mh1.asVarargsCollector(mt1.parameterType(mt1.parameterCount()-1));
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1119
return mh1;
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1120
         * }</pre></blockquote>
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1121
         * where {@code defc} is either {@code receiver.getClass()} or a super
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1122
         * type of that class, in which the requested method is accessible
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1123
         * to the lookup class.
8345
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1124
         * (Note that {@code bindTo} does not preserve variable arity.)
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1125
         * @param receiver the object from which the method is accessed
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1126
         * @param name the name of the method
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1127
         * @param type the type of the method, with the receiver argument omitted
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1128
         * @return the desired method handle
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1129
         * @throws NoSuchMethodException if the method does not exist
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1130
         * @throws IllegalAccessException if access checking fails
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1131
         *                                or if the method's variable arity modifier bit
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1132
         *                                is set and {@code asVarargsCollector} fails
8349
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
  1133
         * @exception SecurityException if a security manager is present and it
e1ba54c43609 7014755: JSR 292 member lookup interaction with security manager
jrose
parents: 8347
diff changeset
  1134
         *                              <a href="MethodHandles.Lookup.html#secmgr">refuses access</a>
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1135
         * @throws NullPointerException if any argument is null
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1136
         * @see MethodHandle#bindTo
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1137
         * @see #findVirtual
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1138
         */
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1139
        public MethodHandle bind(Object receiver, String name, MethodType type) throws NoSuchMethodException, IllegalAccessException {
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1140
            Class<? extends Object> refc = receiver.getClass(); // may get NPE
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1141
            MemberName method = resolveOrFail(REF_invokeSpecial, refc, name, type);
18264
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
  1142
            MethodHandle mh = getDirectMethodNoRestrict(REF_invokeSpecial, refc, method, findBoundCallerClass(method));
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1143
            return mh.bindReceiver(receiver).setVarargs(method);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1144
        }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1145
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1146
        /**
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1147
         * Makes a <a href="MethodHandleInfo.html#directmh">direct method handle</a>
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1148
         * to <i>m</i>, if the lookup class has permission.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1149
         * If <i>m</i> is non-static, the receiver argument is treated as an initial argument.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1150
         * If <i>m</i> is virtual, overriding is respected on every call.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1151
         * Unlike the Core Reflection API, exceptions are <em>not</em> wrapped.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1152
         * The type of the method handle will be that of the method,
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1153
         * with the receiver type prepended (but only if it is non-static).
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1154
         * If the method's {@code accessible} flag is not set,
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1155
         * access checking is performed immediately on behalf of the lookup class.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1156
         * If <i>m</i> is not public, do not share the resulting handle with untrusted parties.
8345
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1157
         * <p>
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1158
         * The returned method handle will have
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1159
         * {@linkplain MethodHandle#asVarargsCollector variable arity} if and only if
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1160
         * the method's variable arity modifier bit ({@code 0x0080}) is set.
20532
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1161
         * <p>
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1162
         * If <i>m</i> is static, and
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1163
         * if the returned method handle is invoked, the method's class will
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1164
         * be initialized, if it has not already been initialized.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1165
         * @param m the reflected method
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1166
         * @return a method handle which can invoke the reflected method
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1167
         * @throws IllegalAccessException if access checking fails
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1168
         *                                or if the method's variable arity modifier bit
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1169
         *                                is set and {@code asVarargsCollector} fails
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1170
         * @throws NullPointerException if the argument is null
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1171
         */
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1172
        public MethodHandle unreflect(Method m) throws IllegalAccessException {
19804
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1173
            if (m.getDeclaringClass() == MethodHandle.class) {
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1174
                MethodHandle mh = unreflectForMH(m);
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1175
                if (mh != null)  return mh;
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1176
            }
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1177
            MemberName method = new MemberName(m);
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1178
            byte refKind = method.getReferenceKind();
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1179
            if (refKind == REF_invokeSpecial)
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1180
                refKind = REF_invokeVirtual;
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1181
            assert(method.isMethod());
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1182
            Lookup lookup = m.isAccessible() ? IMPL_LOOKUP : this;
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1183
            return lookup.getDirectMethodNoSecurityManager(refKind, method.getDeclaringClass(), method, findBoundCallerClass(method));
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1184
        }
19804
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1185
        private MethodHandle unreflectForMH(Method m) {
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1186
            // these names require special lookups because they throw UnsupportedOperationException
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1187
            if (MemberName.isMethodHandleInvokeName(m.getName()))
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1188
                return MethodHandleImpl.fakeMethodHandleInvoke(new MemberName(m));
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1189
            return null;
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1190
        }
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1191
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1192
        /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1193
         * Produces a method handle for a reflected method.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1194
         * It will bypass checks for overriding methods on the receiver,
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1195
         * <a href="MethodHandles.Lookup.html#equiv">as if called</a> from an {@code invokespecial}
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1196
         * instruction from within the explicitly specified {@code specialCaller}.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1197
         * The type of the method handle will be that of the method,
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1198
         * with a suitably restricted receiver type prepended.
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1199
         * (The receiver type will be {@code specialCaller} or a subtype.)
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1200
         * If the method's {@code accessible} flag is not set,
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1201
         * access checking is performed immediately on behalf of the lookup class,
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1202
         * as if {@code invokespecial} instruction were being linked.
8345
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1203
         * <p>
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1204
         * Before method resolution,
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1205
         * if the explicitly specified caller class is not identical with the
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1206
         * lookup class, or if this lookup object does not have
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1207
         * <a href="MethodHandles.Lookup.html#privacc">private access</a>
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1208
         * privileges, the access fails.
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1209
         * <p>
8345
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1210
         * The returned method handle will have
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1211
         * {@linkplain MethodHandle#asVarargsCollector variable arity} if and only if
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1212
         * the method's variable arity modifier bit ({@code 0x0080}) is set.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1213
         * @param m the reflected method
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1214
         * @param specialCaller the class nominally calling the method
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1215
         * @return a method handle which can invoke the reflected method
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1216
         * @throws IllegalAccessException if access checking fails
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1217
         *                                or if the method's variable arity modifier bit
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1218
         *                                is set and {@code asVarargsCollector} fails
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1219
         * @throws NullPointerException if any argument is null
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1220
         */
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1221
        public MethodHandle unreflectSpecial(Method m, Class<?> specialCaller) throws IllegalAccessException {
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1222
            checkSpecialCaller(specialCaller);
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1223
            Lookup specialLookup = this.in(specialCaller);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1224
            MemberName method = new MemberName(m, true);
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1225
            assert(method.isMethod());
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1226
            // ignore m.isAccessible:  this is a new kind of access
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1227
            return specialLookup.getDirectMethodNoSecurityManager(REF_invokeSpecial, method.getDeclaringClass(), method, findBoundCallerClass(method));
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1228
        }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1229
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1230
        /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1231
         * Produces a method handle for a reflected constructor.
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1232
         * The type of the method handle will be that of the constructor,
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1233
         * with the return type changed to the declaring class.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1234
         * The method handle will perform a {@code newInstance} operation,
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1235
         * creating a new instance of the constructor's class on the
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1236
         * arguments passed to the method handle.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1237
         * <p>
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1238
         * If the constructor's {@code accessible} flag is not set,
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1239
         * access checking is performed immediately on behalf of the lookup class.
8345
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1240
         * <p>
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1241
         * The returned method handle will have
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1242
         * {@linkplain MethodHandle#asVarargsCollector variable arity} if and only if
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1243
         * the constructor's variable arity modifier bit ({@code 0x0080}) is set.
20532
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1244
         * <p>
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1245
         * If the returned method handle is invoked, the constructor's class will
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1246
         * be initialized, if it has not already been initialized.
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1247
         * @param c the reflected constructor
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1248
         * @return a method handle which can invoke the reflected constructor
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1249
         * @throws IllegalAccessException if access checking fails
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1250
         *                                or if the method's variable arity modifier bit
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1251
         *                                is set and {@code asVarargsCollector} fails
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1252
         * @throws NullPointerException if the argument is null
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1253
         */
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1254
        public MethodHandle unreflectConstructor(Constructor<?> c) throws IllegalAccessException {
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1255
            MemberName ctor = new MemberName(c);
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1256
            assert(ctor.isConstructor());
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1257
            Lookup lookup = c.isAccessible() ? IMPL_LOOKUP : this;
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1258
            return lookup.getDirectConstructorNoSecurityManager(ctor.getDeclaringClass(), ctor);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1259
        }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1260
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1261
        /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1262
         * Produces a method handle giving read access to a reflected field.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1263
         * The type of the method handle will have a return type of the field's
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1264
         * value type.
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1265
         * If the field is static, the method handle will take no arguments.
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1266
         * Otherwise, its single argument will be the instance containing
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1267
         * the field.
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  1268
         * If the field's {@code accessible} flag is not set,
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1269
         * access checking is performed immediately on behalf of the lookup class.
20532
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1270
         * <p>
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1271
         * If the field is static, and
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1272
         * if the returned method handle is invoked, the field's class will
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1273
         * be initialized, if it has not already been initialized.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1274
         * @param f the reflected field
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1275
         * @return a method handle which can load values from the reflected field
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1276
         * @throws IllegalAccessException if access checking fails
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1277
         * @throws NullPointerException if the argument is null
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1278
         */
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1279
        public MethodHandle unreflectGetter(Field f) throws IllegalAccessException {
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1280
            return unreflectField(f, false);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1281
        }
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1282
        private MethodHandle unreflectField(Field f, boolean isSetter) throws IllegalAccessException {
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1283
            MemberName field = new MemberName(f, isSetter);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1284
            assert(isSetter
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1285
                    ? MethodHandleNatives.refKindIsSetter(field.getReferenceKind())
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1286
                    : MethodHandleNatives.refKindIsGetter(field.getReferenceKind()));
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1287
            Lookup lookup = f.isAccessible() ? IMPL_LOOKUP : this;
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1288
            return lookup.getDirectFieldNoSecurityManager(field.getReferenceKind(), f.getDeclaringClass(), field);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1289
        }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1290
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1291
        /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1292
         * Produces a method handle giving write access to a reflected field.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1293
         * The type of the method handle will have a void return type.
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1294
         * If the field is static, the method handle will take a single
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1295
         * argument, of the field's value type, the value to be stored.
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1296
         * Otherwise, the two arguments will be the instance containing
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1297
         * the field, and the value to be stored.
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  1298
         * If the field's {@code accessible} flag is not set,
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1299
         * access checking is performed immediately on behalf of the lookup class.
20532
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1300
         * <p>
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1301
         * If the field is static, and
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1302
         * if the returned method handle is invoked, the field's class will
50fba462caa5 8024599: JSR 292 direct method handles need to respect initialization rules for static members
jrose
parents: 20531
diff changeset
  1303
         * be initialized, if it has not already been initialized.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1304
         * @param f the reflected field
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1305
         * @return a method handle which can store values into the reflected field
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1306
         * @throws IllegalAccessException if access checking fails
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1307
         * @throws NullPointerException if the argument is null
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1308
         */
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1309
        public MethodHandle unreflectSetter(Field f) throws IllegalAccessException {
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1310
            return unreflectField(f, true);
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1311
        }
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1312
19804
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1313
        /**
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1314
         * Cracks a <a href="MethodHandleInfo.html#directmh">direct method handle</a>
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1315
         * created by this lookup object or a similar one.
19804
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1316
         * Security and access checks are performed to ensure that this lookup object
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1317
         * is capable of reproducing the target method handle.
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1318
         * This means that the cracking may fail if target is a direct method handle
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1319
         * but was created by an unrelated lookup object.
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1320
         * This can happen if the method handle is <a href="MethodHandles.Lookup.html#callsens">caller sensitive</a>
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1321
         * and was created by a lookup object for a different class.
19804
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1322
         * @param target a direct method handle to crack into symbolic reference components
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1323
         * @return a symbolic reference which can be used to reconstruct this method handle from this lookup object
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1324
         * @exception SecurityException if a security manager is present and it
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1325
         *                              <a href="MethodHandles.Lookup.html#secmgr">refuses access</a>
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1326
         * @throws IllegalArgumentException if the target is not a direct method handle or if access checking fails
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1327
         * @exception NullPointerException if the target is {@code null}
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1328
         * @see MethodHandleInfo
19804
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1329
         * @since 1.8
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1330
         */
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1331
        public MethodHandleInfo revealDirect(MethodHandle target) {
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1332
            MemberName member = target.internalMemberName();
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1333
            if (member == null || (!member.isResolved() && !member.isMethodHandleInvoke()))
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1334
                throw newIllegalArgumentException("not a direct method handle");
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1335
            Class<?> defc = member.getDeclaringClass();
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1336
            byte refKind = member.getReferenceKind();
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1337
            assert(MethodHandleNatives.refKindIsValid(refKind));
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1338
            if (refKind == REF_invokeSpecial && !target.isInvokeSpecial())
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1339
                // Devirtualized method invocation is usually formally virtual.
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1340
                // To avoid creating extra MemberName objects for this common case,
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1341
                // we encode this extra degree of freedom using MH.isInvokeSpecial.
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1342
                refKind = REF_invokeVirtual;
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1343
            if (refKind == REF_invokeVirtual && defc.isInterface())
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1344
                // Symbolic reference is through interface but resolves to Object method (toString, etc.)
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1345
                refKind = REF_invokeInterface;
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1346
            // Check SM permissions and member access before cracking.
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1347
            try {
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1348
                checkAccess(refKind, defc, member);
19804
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1349
                checkSecurityManager(defc, member);
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1350
            } catch (IllegalAccessException ex) {
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1351
                throw new IllegalArgumentException(ex);
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1352
            }
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1353
            if (allowedModes != TRUSTED && member.isCallerSensitive()) {
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1354
                Class<?> callerClass = target.internalCallerClass();
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1355
                if (!hasPrivateAccess() || callerClass != lookupClass())
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1356
                    throw new IllegalArgumentException("method handle is caller sensitive: "+callerClass);
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1357
            }
19804
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1358
            // Produce the handle to the results.
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1359
            return new InfoFromMemberName(this, member, refKind);
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1360
        }
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1361
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1362
        /// Helper methods, all package-private.
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1363
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1364
        MemberName resolveOrFail(byte refKind, Class<?> refc, String name, Class<?> type) throws NoSuchFieldException, IllegalAccessException {
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1365
            checkSymbolicClass(refc);  // do this before attempting to resolve
20527
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1366
            name.getClass();  // NPE
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1367
            type.getClass();  // NPE
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1368
            return IMPL_NAMES.resolveOrFail(refKind, new MemberName(refc, name, type, refKind), lookupClassOrNull(),
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1369
                                            NoSuchFieldException.class);
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1370
        }
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1371
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1372
        MemberName resolveOrFail(byte refKind, Class<?> refc, String name, MethodType type) throws NoSuchMethodException, IllegalAccessException {
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1373
            checkSymbolicClass(refc);  // do this before attempting to resolve
20527
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1374
            name.getClass();  // NPE
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1375
            type.getClass();  // NPE
20531
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
  1376
            checkMethodName(refKind, name);  // NPE check on name
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1377
            return IMPL_NAMES.resolveOrFail(refKind, new MemberName(refc, name, type, refKind), lookupClassOrNull(),
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1378
                                            NoSuchMethodException.class);
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1379
        }
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1380
20527
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1381
        MemberName resolveOrFail(byte refKind, MemberName member) throws ReflectiveOperationException {
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1382
            checkSymbolicClass(member.getDeclaringClass());  // do this before attempting to resolve
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1383
            member.getName().getClass();  // NPE
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1384
            member.getType().getClass();  // NPE
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1385
            return IMPL_NAMES.resolveOrFail(refKind, member, lookupClassOrNull(),
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1386
                                            ReflectiveOperationException.class);
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1387
        }
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1388
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1389
        void checkSymbolicClass(Class<?> refc) throws IllegalAccessException {
20527
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1390
            refc.getClass();  // NPE
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1391
            Class<?> caller = lookupClassOrNull();
13044
8411854afc2b 7165628: Issues with java.lang.invoke.MethodHandles.Lookup
jrose
parents: 11535
diff changeset
  1392
            if (caller != null && !VerifyAccess.isClassAccessible(refc, caller, allowedModes))
8821
2836ee97ee27 6839872: remove implementation inheritance from JSR 292 APIs
jrose
parents: 8349
diff changeset
  1393
                throw new MemberName(refc).makeAccessException("symbolic reference class is not public", this);
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1394
        }
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1395
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1396
        /** Check name for an illegal leading "&lt;" character. */
20531
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
  1397
        void checkMethodName(byte refKind, String name) throws NoSuchMethodException {
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
  1398
            if (name.startsWith("<") && refKind != REF_newInvokeSpecial)
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
  1399
                throw new NoSuchMethodException("illegal method name: "+name);
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
  1400
        }
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
  1401
14c2a04f21e6 8001108: an attempt to use "<init>" as a method name should elicit NoSuchMethodException
jrose
parents: 20530
diff changeset
  1402
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1403
        /**
16118
9f3390f42157 8006439: Improve MethodHandles coverage
vlivanov
parents: 14222
diff changeset
  1404
         * Find my trustable caller class if m is a caller sensitive method.
9f3390f42157 8006439: Improve MethodHandles coverage
vlivanov
parents: 14222
diff changeset
  1405
         * If this lookup object has private access, then the caller class is the lookupClass.
18264
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
  1406
         * Otherwise, if m is caller-sensitive, throw IllegalAccessException.
16118
9f3390f42157 8006439: Improve MethodHandles coverage
vlivanov
parents: 14222
diff changeset
  1407
         */
18264
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
  1408
        Class<?> findBoundCallerClass(MemberName m) throws IllegalAccessException {
16118
9f3390f42157 8006439: Improve MethodHandles coverage
vlivanov
parents: 14222
diff changeset
  1409
            Class<?> callerClass = null;
9f3390f42157 8006439: Improve MethodHandles coverage
vlivanov
parents: 14222
diff changeset
  1410
            if (MethodHandleNatives.isCallerSensitive(m)) {
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1411
                // Only lookups with private access are allowed to resolve caller-sensitive methods
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1412
                if (hasPrivateAccess()) {
18264
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
  1413
                    callerClass = lookupClass;
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
  1414
                } else {
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
  1415
                    throw new IllegalAccessException("Attempt to lookup caller-sensitive method using restricted lookup object");
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
  1416
                }
16118
9f3390f42157 8006439: Improve MethodHandles coverage
vlivanov
parents: 14222
diff changeset
  1417
            }
9f3390f42157 8006439: Improve MethodHandles coverage
vlivanov
parents: 14222
diff changeset
  1418
            return callerClass;
9f3390f42157 8006439: Improve MethodHandles coverage
vlivanov
parents: 14222
diff changeset
  1419
        }
16906
44dfee24cb71 8010117: Annotate jdk caller sensitive methods with @sun.reflect.CallerSensitive
mchung
parents: 16898
diff changeset
  1420
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1421
        private boolean hasPrivateAccess() {
18264
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
  1422
            return (allowedModes & PRIVATE) != 0;
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
  1423
        }
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
  1424
16906
44dfee24cb71 8010117: Annotate jdk caller sensitive methods with @sun.reflect.CallerSensitive
mchung
parents: 16898
diff changeset
  1425
        /**
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1426
         * Perform necessary <a href="MethodHandles.Lookup.html#secmgr">access checks</a>.
16118
9f3390f42157 8006439: Improve MethodHandles coverage
vlivanov
parents: 14222
diff changeset
  1427
         * Determines a trustable caller class to compare with refc, the symbolic reference class.
9f3390f42157 8006439: Improve MethodHandles coverage
vlivanov
parents: 14222
diff changeset
  1428
         * If this lookup object has private access, then the caller class is the lookupClass.
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1429
         */
18264
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
  1430
        void checkSecurityManager(Class<?> refc, MemberName m) {
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1431
            SecurityManager smgr = System.getSecurityManager();
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1432
            if (smgr == null)  return;
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1433
            if (allowedModes == TRUSTED)  return;
16906
44dfee24cb71 8010117: Annotate jdk caller sensitive methods with @sun.reflect.CallerSensitive
mchung
parents: 16898
diff changeset
  1434
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1435
            // Step 1:
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1436
            boolean fullPowerLookup = hasPrivateAccess();
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1437
            if (!fullPowerLookup ||
18264
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
  1438
                !VerifyAccess.classLoaderIsAncestor(lookupClass, refc)) {
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
  1439
                ReflectUtil.checkPackageAccess(refc);
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
  1440
            }
16906
44dfee24cb71 8010117: Annotate jdk caller sensitive methods with @sun.reflect.CallerSensitive
mchung
parents: 16898
diff changeset
  1441
18766
28c62f5e9a47 8007035: deprecate public void SecurityManager.checkMemberAccess(Class<?> clazz, int which)
mchung
parents: 18569
diff changeset
  1442
            // Step 2:
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1443
            if (m.isPublic()) return;
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1444
            if (!fullPowerLookup) {
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1445
                smgr.checkPermission(SecurityConstants.CHECK_MEMBER_ACCESS_PERMISSION);
16906
44dfee24cb71 8010117: Annotate jdk caller sensitive methods with @sun.reflect.CallerSensitive
mchung
parents: 16898
diff changeset
  1446
            }
44dfee24cb71 8010117: Annotate jdk caller sensitive methods with @sun.reflect.CallerSensitive
mchung
parents: 16898
diff changeset
  1447
18766
28c62f5e9a47 8007035: deprecate public void SecurityManager.checkMemberAccess(Class<?> clazz, int which)
mchung
parents: 18569
diff changeset
  1448
            // Step 3:
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1449
            Class<?> defc = m.getDeclaringClass();
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1450
            if (!fullPowerLookup && defc != refc) {
18264
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
  1451
                ReflectUtil.checkPackageAccess(defc);
286a7973575a 8009424: Restrict publicLookup with additional checks
twisti
parents: 16906
diff changeset
  1452
            }
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1453
        }
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1454
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1455
        void checkMethod(byte refKind, Class<?> refc, MemberName m) throws IllegalAccessException {
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1456
            boolean wantStatic = (refKind == REF_invokeStatic);
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1457
            String message;
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1458
            if (m.isConstructor())
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1459
                message = "expected a method, not a constructor";
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1460
            else if (!m.isMethod())
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1461
                message = "expected a method";
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1462
            else if (wantStatic != m.isStatic())
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1463
                message = wantStatic ? "expected a static method" : "expected a non-static method";
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1464
            else
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1465
                { checkAccess(refKind, refc, m); return; }
8821
2836ee97ee27 6839872: remove implementation inheritance from JSR 292 APIs
jrose
parents: 8349
diff changeset
  1466
            throw m.makeAccessException(message, this);
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1467
        }
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1468
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1469
        void checkField(byte refKind, Class<?> refc, MemberName m) throws IllegalAccessException {
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1470
            boolean wantStatic = !MethodHandleNatives.refKindHasReceiver(refKind);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1471
            String message;
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1472
            if (wantStatic != m.isStatic())
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1473
                message = wantStatic ? "expected a static field" : "expected a non-static field";
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1474
            else
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1475
                { checkAccess(refKind, refc, m); return; }
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1476
            throw m.makeAccessException(message, this);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1477
        }
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1478
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1479
        /** Check public/protected/private bits on the symbolic reference class and its member. */
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1480
        void checkAccess(byte refKind, Class<?> refc, MemberName m) throws IllegalAccessException {
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1481
            assert(m.referenceKindIsConsistentWith(refKind) &&
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1482
                   MethodHandleNatives.refKindIsValid(refKind) &&
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1483
                   (MethodHandleNatives.refKindIsField(refKind) == m.isField()));
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1484
            int allowedModes = this.allowedModes;
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1485
            if (allowedModes == TRUSTED)  return;
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1486
            int mods = m.getModifiers();
20528
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1487
            if (Modifier.isProtected(mods) &&
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1488
                    refKind == REF_invokeVirtual &&
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1489
                    m.getDeclaringClass() == Object.class &&
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1490
                    m.getName().equals("clone") &&
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1491
                    refc.isArray()) {
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1492
                // The JVM does this hack also.
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1493
                // (See ClassVerifier::verify_invoke_instructions
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1494
                // and LinkResolver::check_method_accessability.)
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1495
                // Because the JVM does not allow separate methods on array types,
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1496
                // there is no separate method for int[].clone.
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1497
                // All arrays simply inherit Object.clone.
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1498
                // But for access checking logic, we make Object.clone
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1499
                // (normally protected) appear to be public.
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1500
                // Later on, when the DirectMethodHandle is created,
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1501
                // its leading argument will be restricted to the
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1502
                // requested array type.
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1503
                // N.B. The return type is not adjusted, because
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1504
                // that is *not* the bytecode behavior.
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1505
                mods ^= Modifier.PROTECTED | Modifier.PUBLIC;
0b1e2130d3f7 8001105: findVirtual of Object[].clone produces internal error
jrose
parents: 20527
diff changeset
  1506
            }
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1507
            if (Modifier.isFinal(mods) &&
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1508
                    MethodHandleNatives.refKindIsSetter(refKind))
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1509
                throw m.makeAccessException("unexpected set of a final field", this);
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1510
            if (Modifier.isPublic(mods) && Modifier.isPublic(refc.getModifiers()) && allowedModes != 0)
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1511
                return;  // common case
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1512
            int requestedModes = fixmods(mods);  // adjust 0 => PACKAGE
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1513
            if ((requestedModes & allowedModes) != 0) {
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1514
                if (VerifyAccess.isMemberAccessible(refc, m.getDeclaringClass(),
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1515
                                                    mods, lookupClass(), allowedModes))
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1516
                    return;
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1517
            } else {
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1518
                // Protected members can also be checked as if they were package-private.
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1519
                if ((requestedModes & PROTECTED) != 0 && (allowedModes & PACKAGE) != 0
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1520
                        && VerifyAccess.isSamePackage(m.getDeclaringClass(), lookupClass()))
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1521
                    return;
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1522
            }
8821
2836ee97ee27 6839872: remove implementation inheritance from JSR 292 APIs
jrose
parents: 8349
diff changeset
  1523
            throw m.makeAccessException(accessFailedMessage(refc, m), this);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1524
        }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1525
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1526
        String accessFailedMessage(Class<?> refc, MemberName m) {
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1527
            Class<?> defc = m.getDeclaringClass();
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1528
            int mods = m.getModifiers();
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1529
            // check the class first:
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1530
            boolean classOK = (Modifier.isPublic(defc.getModifiers()) &&
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1531
                               (defc == refc ||
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1532
                                Modifier.isPublic(refc.getModifiers())));
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1533
            if (!classOK && (allowedModes & PACKAGE) != 0) {
13044
8411854afc2b 7165628: Issues with java.lang.invoke.MethodHandles.Lookup
jrose
parents: 11535
diff changeset
  1534
                classOK = (VerifyAccess.isClassAccessible(defc, lookupClass(), ALL_MODES) &&
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1535
                           (defc == refc ||
13044
8411854afc2b 7165628: Issues with java.lang.invoke.MethodHandles.Lookup
jrose
parents: 11535
diff changeset
  1536
                            VerifyAccess.isClassAccessible(refc, lookupClass(), ALL_MODES)));
8347
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1537
            }
e5daa5772ffd 7013730: JSR 292 reflective operations should report errors with standard exception types
jrose
parents: 8346
diff changeset
  1538
            if (!classOK)
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1539
                return "class is not public";
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1540
            if (Modifier.isPublic(mods))
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1541
                return "access to public member failed";  // (how?)
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1542
            if (Modifier.isPrivate(mods))
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1543
                return "member is private";
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1544
            if (Modifier.isProtected(mods))
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1545
                return "member is protected";
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1546
            return "member is private to package";
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1547
        }
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1548
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1549
        private static final boolean ALLOW_NESTMATE_ACCESS = false;
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1550
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1551
        private void checkSpecialCaller(Class<?> specialCaller) throws IllegalAccessException {
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1552
            int allowedModes = this.allowedModes;
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1553
            if (allowedModes == TRUSTED)  return;
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1554
            if (!hasPrivateAccess()
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1555
                || (specialCaller != lookupClass()
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1556
                    && !(ALLOW_NESTMATE_ACCESS &&
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1557
                         VerifyAccess.isSamePackageMember(specialCaller, lookupClass()))))
8821
2836ee97ee27 6839872: remove implementation inheritance from JSR 292 APIs
jrose
parents: 8349
diff changeset
  1558
                throw new MemberName(specialCaller).
2836ee97ee27 6839872: remove implementation inheritance from JSR 292 APIs
jrose
parents: 8349
diff changeset
  1559
                    makeAccessException("no private access for invokespecial", this);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1560
        }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1561
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1562
        private boolean restrictProtectedReceiver(MemberName method) {
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1563
            // The accessing class only has the right to use a protected member
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1564
            // on itself or a subclass.  Enforce that restriction, from JVMS 5.4.4, etc.
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1565
            if (!method.isProtected() || method.isStatic()
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1566
                || allowedModes == TRUSTED
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1567
                || method.getDeclaringClass() == lookupClass()
9731
d0f7a3e441c4 7044892: JSR 292: API entry points sometimes throw the wrong exceptions or doesn't throw the expected one
jrose
parents: 9730
diff changeset
  1568
                || VerifyAccess.isSamePackage(method.getDeclaringClass(), lookupClass())
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1569
                || (ALLOW_NESTMATE_ACCESS &&
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1570
                    VerifyAccess.isSamePackageMember(method.getDeclaringClass(), lookupClass())))
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1571
                return false;
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1572
            return true;
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1573
        }
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1574
        private MethodHandle restrictReceiver(MemberName method, MethodHandle mh, Class<?> caller) throws IllegalAccessException {
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1575
            assert(!method.isStatic());
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1576
            // receiver type of mh is too wide; narrow to caller
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1577
            if (!method.getDeclaringClass().isAssignableFrom(caller)) {
8821
2836ee97ee27 6839872: remove implementation inheritance from JSR 292 APIs
jrose
parents: 8349
diff changeset
  1578
                throw method.makeAccessException("caller class must be a subclass below the method", caller);
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1579
            }
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1580
            MethodType rawType = mh.type();
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1581
            if (rawType.parameterType(0) == caller)  return mh;
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1582
            MethodType narrowType = rawType.changeParameterType(0, caller);
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1583
            return mh.viewAsType(narrowType);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1584
        }
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1585
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1586
        /** Check access and get the requested method. */
16118
9f3390f42157 8006439: Improve MethodHandles coverage
vlivanov
parents: 14222
diff changeset
  1587
        private MethodHandle getDirectMethod(byte refKind, Class<?> refc, MemberName method, Class<?> callerClass) throws IllegalAccessException {
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1588
            final boolean doRestrict    = true;
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1589
            final boolean checkSecurity = true;
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1590
            return getDirectMethodCommon(refKind, refc, method, checkSecurity, doRestrict, callerClass);
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1591
        }
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1592
        /** Check access and get the requested method, eliding receiver narrowing rules. */
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1593
        private MethodHandle getDirectMethodNoRestrict(byte refKind, Class<?> refc, MemberName method, Class<?> callerClass) throws IllegalAccessException {
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1594
            final boolean doRestrict    = false;
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1595
            final boolean checkSecurity = true;
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1596
            return getDirectMethodCommon(refKind, refc, method, checkSecurity, doRestrict, callerClass);
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1597
        }
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1598
        /** Check access and get the requested method, eliding security manager checks. */
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1599
        private MethodHandle getDirectMethodNoSecurityManager(byte refKind, Class<?> refc, MemberName method, Class<?> callerClass) throws IllegalAccessException {
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1600
            final boolean doRestrict    = true;
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1601
            final boolean checkSecurity = false;  // not needed for reflection or for linking CONSTANT_MH constants
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1602
            return getDirectMethodCommon(refKind, refc, method, checkSecurity, doRestrict, callerClass);
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1603
        }
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1604
        /** Common code for all methods; do not call directly except from immediately above. */
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1605
        private MethodHandle getDirectMethodCommon(byte refKind, Class<?> refc, MemberName method,
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1606
                                                   boolean checkSecurity,
16118
9f3390f42157 8006439: Improve MethodHandles coverage
vlivanov
parents: 14222
diff changeset
  1607
                                                   boolean doRestrict, Class<?> callerClass) throws IllegalAccessException {
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1608
            checkMethod(refKind, refc, method);
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1609
            // Optionally check with the security manager; this isn't needed for unreflect* calls.
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1610
            if (checkSecurity)
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1611
                checkSecurityManager(refc, method);
19804
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1612
            assert(!method.isMethodHandleInvoke());
16898
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1613
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1614
            Class<?> refcAsSuper;
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1615
            if (refKind == REF_invokeSpecial &&
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1616
                refc != lookupClass() &&
19804
83170920c07b 8008688: Make MethodHandleInfo public
rfield
parents: 18766
diff changeset
  1617
                !refc.isInterface() &&
16898
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1618
                refc != (refcAsSuper = lookupClass().getSuperclass()) &&
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1619
                refc.isAssignableFrom(lookupClass())) {
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1620
                assert(!method.getName().equals("<init>"));  // not this code path
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1621
                // Per JVMS 6.5, desc. of invokespecial instruction:
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1622
                // If the method is in a superclass of the LC,
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1623
                // and if our original search was above LC.super,
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1624
                // repeat the search (symbolic lookup) from LC.super.
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1625
                // FIXME: MemberName.resolve should handle this instead.
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1626
                MemberName m2 = new MemberName(refcAsSuper,
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1627
                                               method.getName(),
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1628
                                               method.getMethodType(),
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1629
                                               REF_invokeSpecial);
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1630
                m2 = IMPL_NAMES.resolveOrNull(refKind, m2, lookupClassOrNull());
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1631
                if (m2 == null)  throw new InternalError(method.toString());
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1632
                method = m2;
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1633
                refc = refcAsSuper;
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1634
                // redo basic checks
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1635
                checkMethod(refKind, refc, method);
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1636
            }
b321dfd1163f 8008140: Better method handle resolution
vlivanov
parents: 16123
diff changeset
  1637
16030
265a0d86c9ff 7087570: java.lang.invoke.MemberName information wrong for method handles created with findConstructor
kmo
parents: 14222
diff changeset
  1638
            MethodHandle mh = DirectMethodHandle.make(refKind, refc, method);
16118
9f3390f42157 8006439: Improve MethodHandles coverage
vlivanov
parents: 14222
diff changeset
  1639
            mh = maybeBindCaller(method, mh, callerClass);
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1640
            mh = mh.setVarargs(method);
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1641
            // Optionally narrow the receiver argument to refc using restrictReceiver.
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1642
            if (doRestrict &&
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1643
                   (refKind == REF_invokeSpecial ||
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1644
                       (MethodHandleNatives.refKindHasReceiver(refKind) &&
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1645
                           restrictProtectedReceiver(method))))
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1646
                mh = restrictReceiver(method, mh, lookupClass());
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1647
            return mh;
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1648
        }
16118
9f3390f42157 8006439: Improve MethodHandles coverage
vlivanov
parents: 14222
diff changeset
  1649
        private MethodHandle maybeBindCaller(MemberName method, MethodHandle mh,
9f3390f42157 8006439: Improve MethodHandles coverage
vlivanov
parents: 14222
diff changeset
  1650
                                             Class<?> callerClass)
9f3390f42157 8006439: Improve MethodHandles coverage
vlivanov
parents: 14222
diff changeset
  1651
                                             throws IllegalAccessException {
14222
58f55d4dde46 7196190: Improve method of handling MethodHandles
jrose
parents: 13610
diff changeset
  1652
            if (allowedModes == TRUSTED || !MethodHandleNatives.isCallerSensitive(method))
58f55d4dde46 7196190: Improve method of handling MethodHandles
jrose
parents: 13610
diff changeset
  1653
                return mh;
58f55d4dde46 7196190: Improve method of handling MethodHandles
jrose
parents: 13610
diff changeset
  1654
            Class<?> hostClass = lookupClass;
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1655
            if (!hasPrivateAccess())  // caller must have private access
16118
9f3390f42157 8006439: Improve MethodHandles coverage
vlivanov
parents: 14222
diff changeset
  1656
                hostClass = callerClass;  // callerClass came from a security manager style stack walk
14222
58f55d4dde46 7196190: Improve method of handling MethodHandles
jrose
parents: 13610
diff changeset
  1657
            MethodHandle cbmh = MethodHandleImpl.bindCaller(mh, hostClass);
58f55d4dde46 7196190: Improve method of handling MethodHandles
jrose
parents: 13610
diff changeset
  1658
            // Note: caller will apply varargs after this step happens.
58f55d4dde46 7196190: Improve method of handling MethodHandles
jrose
parents: 13610
diff changeset
  1659
            return cbmh;
58f55d4dde46 7196190: Improve method of handling MethodHandles
jrose
parents: 13610
diff changeset
  1660
        }
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1661
        /** Check access and get the requested field. */
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1662
        private MethodHandle getDirectField(byte refKind, Class<?> refc, MemberName field) throws IllegalAccessException {
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1663
            final boolean checkSecurity = true;
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1664
            return getDirectFieldCommon(refKind, refc, field, checkSecurity);
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1665
        }
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1666
        /** Check access and get the requested field, eliding security manager checks. */
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1667
        private MethodHandle getDirectFieldNoSecurityManager(byte refKind, Class<?> refc, MemberName field) throws IllegalAccessException {
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1668
            final boolean checkSecurity = false;  // not needed for reflection or for linking CONSTANT_MH constants
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1669
            return getDirectFieldCommon(refKind, refc, field, checkSecurity);
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1670
        }
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1671
        /** Common code for all fields; do not call directly except from immediately above. */
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1672
        private MethodHandle getDirectFieldCommon(byte refKind, Class<?> refc, MemberName field,
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1673
                                                  boolean checkSecurity) throws IllegalAccessException {
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1674
            checkField(refKind, refc, field);
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1675
            // Optionally check with the security manager; this isn't needed for unreflect* calls.
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1676
            if (checkSecurity)
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1677
                checkSecurityManager(refc, field);
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1678
            MethodHandle mh = DirectMethodHandle.make(refc, field);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1679
            boolean doRestrict = (MethodHandleNatives.refKindHasReceiver(refKind) &&
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1680
                                    restrictProtectedReceiver(field));
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1681
            if (doRestrict)
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1682
                mh = restrictReceiver(field, mh, lookupClass());
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1683
            return mh;
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1684
        }
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1685
        /** Check access and get the requested constructor. */
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1686
        private MethodHandle getDirectConstructor(Class<?> refc, MemberName ctor) throws IllegalAccessException {
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1687
            final boolean checkSecurity = true;
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1688
            return getDirectConstructorCommon(refc, ctor, checkSecurity);
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1689
        }
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1690
        /** Check access and get the requested constructor, eliding security manager checks. */
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1691
        private MethodHandle getDirectConstructorNoSecurityManager(Class<?> refc, MemberName ctor) throws IllegalAccessException {
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1692
            final boolean checkSecurity = false;  // not needed for reflection or for linking CONSTANT_MH constants
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1693
            return getDirectConstructorCommon(refc, ctor, checkSecurity);
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1694
        }
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1695
        /** Common code for all constructors; do not call directly except from immediately above. */
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1696
        private MethodHandle getDirectConstructorCommon(Class<?> refc, MemberName ctor,
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1697
                                                  boolean checkSecurity) throws IllegalAccessException {
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1698
            assert(ctor.isConstructor());
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1699
            checkAccess(REF_newInvokeSpecial, refc, ctor);
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1700
            // Optionally check with the security manager; this isn't needed for unreflect* calls.
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1701
            if (checkSecurity)
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1702
                checkSecurityManager(refc, ctor);
14222
58f55d4dde46 7196190: Improve method of handling MethodHandles
jrose
parents: 13610
diff changeset
  1703
            assert(!MethodHandleNatives.isCallerSensitive(ctor));  // maybeBindCaller not relevant here
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1704
            return DirectMethodHandle.make(ctor).setVarargs(ctor);
5722
4ada807383c8 6939134: JSR 292 adjustments to method handle invocation
jrose
parents: 4537
diff changeset
  1705
        }
9780
6fc3b49cfee4 7050328: (jsr-292) findConstructor throws ExceptionInInitializerError if run under SecurityManager
jrose
parents: 9752
diff changeset
  1706
6fc3b49cfee4 7050328: (jsr-292) findConstructor throws ExceptionInInitializerError if run under SecurityManager
jrose
parents: 9752
diff changeset
  1707
        /** Hook called from the JVM (via MethodHandleNatives) to link MH constants:
6fc3b49cfee4 7050328: (jsr-292) findConstructor throws ExceptionInInitializerError if run under SecurityManager
jrose
parents: 9752
diff changeset
  1708
         */
6fc3b49cfee4 7050328: (jsr-292) findConstructor throws ExceptionInInitializerError if run under SecurityManager
jrose
parents: 9752
diff changeset
  1709
        /*non-public*/
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1710
        MethodHandle linkMethodHandleConstant(byte refKind, Class<?> defc, String name, Object type) throws ReflectiveOperationException {
20527
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1711
            if (!(type instanceof Class || type instanceof MethodType))
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1712
                throw new InternalError("unresolved MemberName");
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1713
            MemberName member = new MemberName(refKind, defc, name, type);
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1714
            MethodHandle mh = LOOKASIDE_TABLE.get(member);
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1715
            if (mh != null) {
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1716
                checkSymbolicClass(defc);
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1717
                return mh;
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1718
            }
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1719
            MemberName resolved = resolveOrFail(refKind, member);
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1720
            mh = getDirectMethodForConstant(refKind, defc, resolved);
20527
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1721
            if (mh instanceof DirectMethodHandle
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1722
                    && canBeCached(refKind, defc, resolved)) {
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1723
                MemberName key = mh.internalMemberName();
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1724
                if (key != null) {
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1725
                    key = key.asNormalOriginal();
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1726
                }
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1727
                if (member.equals(key)) {  // better safe than sorry
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1728
                    LOOKASIDE_TABLE.put(key, (DirectMethodHandle) mh);
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1729
                }
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1730
            }
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1731
            return mh;
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1732
        }
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1733
        private
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1734
        boolean canBeCached(byte refKind, Class<?> defc, MemberName member) {
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1735
            if (refKind == REF_invokeSpecial) {
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1736
                return false;
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1737
            }
20527
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1738
            if (!Modifier.isPublic(defc.getModifiers()) ||
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1739
                    !Modifier.isPublic(member.getDeclaringClass().getModifiers()) ||
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1740
                    !member.isPublic() ||
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1741
                    member.isCallerSensitive()) {
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1742
                return false;
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1743
            }
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1744
            ClassLoader loader = defc.getClassLoader();
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1745
            if (!sun.misc.VM.isSystemDomainLoader(loader)) {
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1746
                ClassLoader sysl = ClassLoader.getSystemClassLoader();
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1747
                boolean found = false;
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1748
                while (sysl != null) {
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1749
                    if (loader == sysl) { found = true; break; }
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1750
                    sysl = sysl.getParent();
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1751
                }
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1752
                if (!found) {
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1753
                    return false;
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1754
                }
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1755
            }
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1756
            try {
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1757
                MemberName resolved2 = publicLookup().resolveOrFail(refKind,
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1758
                    new MemberName(refKind, defc, member.getName(), member.getType()));
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1759
                checkSecurityManager(defc, resolved2);
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1760
            } catch (ReflectiveOperationException | SecurityException ex) {
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1761
                return false;
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1762
            }
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1763
            return true;
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1764
        }
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1765
        private
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1766
        MethodHandle getDirectMethodForConstant(byte refKind, Class<?> defc, MemberName member)
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1767
                throws ReflectiveOperationException {
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1768
            if (MethodHandleNatives.refKindIsField(refKind)) {
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1769
                return getDirectFieldNoSecurityManager(refKind, defc, member);
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1770
            } else if (MethodHandleNatives.refKindIsMethod(refKind)) {
20841
2b188911d712 8022066: Evaluation of method reference to signature polymorphic method crashes VM
twisti
parents: 20831
diff changeset
  1771
                if (defc == MethodHandle.class && refKind == REF_invokeVirtual) {
20853
chegar
parents: 20535 20851
diff changeset
  1772
                    MethodHandle mh = findVirtualForMH(member.getName(), member.getMethodType());
chegar
parents: 20535 20851
diff changeset
  1773
                    if (mh != null) {
chegar
parents: 20535 20851
diff changeset
  1774
                        return mh;
chegar
parents: 20535 20851
diff changeset
  1775
                    }
20841
2b188911d712 8022066: Evaluation of method reference to signature polymorphic method crashes VM
twisti
parents: 20831
diff changeset
  1776
                }
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1777
                return getDirectMethodNoSecurityManager(refKind, defc, member, lookupClass);
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1778
            } else if (refKind == REF_newInvokeSpecial) {
20534
da86f7904e6d 8025112: JSR 292 spec updates for security manager and caller sensitivity
jrose
parents: 20533
diff changeset
  1779
                return getDirectConstructorNoSecurityManager(defc, member);
9780
6fc3b49cfee4 7050328: (jsr-292) findConstructor throws ExceptionInInitializerError if run under SecurityManager
jrose
parents: 9752
diff changeset
  1780
            }
6fc3b49cfee4 7050328: (jsr-292) findConstructor throws ExceptionInInitializerError if run under SecurityManager
jrose
parents: 9752
diff changeset
  1781
            // oops
20527
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1782
            throw newIllegalArgumentException("bad MethodHandle constant #"+member);
9780
6fc3b49cfee4 7050328: (jsr-292) findConstructor throws ExceptionInInitializerError if run under SecurityManager
jrose
parents: 9752
diff changeset
  1783
        }
20527
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1784
d241258cfbcb 8024761: JSR 292 improve performance of generic invocation
jrose
parents: 19804
diff changeset
  1785
        static ConcurrentHashMap<MemberName, DirectMethodHandle> LOOKASIDE_TABLE = new ConcurrentHashMap<>();
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1786
    }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1787
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1788
    /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1789
     * Produces a method handle giving read access to elements of an array.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1790
     * The type of the method handle will have a return type of the array's
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1791
     * element type.  Its first argument will be the array type,
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1792
     * and the second will be {@code int}.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1793
     * @param arrayClass an array type
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1794
     * @return a method handle which can load values from the given array type
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1795
     * @throws NullPointerException if the argument is null
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1796
     * @throws  IllegalArgumentException if arrayClass is not an array type
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1797
     */
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1798
    public static
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1799
    MethodHandle arrayElementGetter(Class<?> arrayClass) throws IllegalArgumentException {
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1800
        return MethodHandleImpl.makeArrayElementAccessor(arrayClass, false);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1801
    }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1802
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1803
    /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1804
     * Produces a method handle giving write access to elements of an array.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1805
     * The type of the method handle will have a void return type.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1806
     * Its last argument will be the array's element type.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1807
     * The first and second arguments will be the array type and int.
18569
0e46c17766b7 8019357: Fix doclint warnings in java.lang.invoke
darcy
parents: 18274
diff changeset
  1808
     * @param arrayClass the class of an array
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1809
     * @return a method handle which can store values into the array type
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1810
     * @throws NullPointerException if the argument is null
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1811
     * @throws IllegalArgumentException if arrayClass is not an array type
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1812
     */
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1813
    public static
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1814
    MethodHandle arrayElementSetter(Class<?> arrayClass) throws IllegalArgumentException {
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1815
        return MethodHandleImpl.makeArrayElementAccessor(arrayClass, true);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1816
    }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1817
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1818
    /// method handle invocation (reflective style)
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1819
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1820
    /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1821
     * Produces a method handle which will invoke any method handle of the
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1822
     * given {@code type}, with a given number of trailing arguments replaced by
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1823
     * a single trailing {@code Object[]} array.
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1824
     * The resulting invoker will be a method handle with the following
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1825
     * arguments:
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1826
     * <ul>
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1827
     * <li>a single {@code MethodHandle} target
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1828
     * <li>zero or more leading values (counted by {@code leadingArgCount})
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1829
     * <li>an {@code Object[]} array containing trailing arguments
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1830
     * </ul>
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1831
     * <p>
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1832
     * The invoker will invoke its target like a call to {@link MethodHandle#invoke invoke} with
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1833
     * the indicated {@code type}.
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1834
     * That is, if the target is exactly of the given {@code type}, it will behave
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1835
     * like {@code invokeExact}; otherwise it behave as if {@link MethodHandle#asType asType}
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1836
     * is used to convert the target to the required {@code type}.
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1837
     * <p>
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1838
     * The type of the returned invoker will not be the given {@code type}, but rather
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1839
     * will have all parameters except the first {@code leadingArgCount}
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1840
     * replaced by a single array of type {@code Object[]}, which will be
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1841
     * the final parameter.
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1842
     * <p>
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1843
     * Before invoking its target, the invoker will spread the final array, apply
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1844
     * reference casts as necessary, and unbox and widen primitive arguments.
20530
b54a1f5cd35f 8001109: arity mismatch on a call to spreader method handle should elicit IllegalArgumentException
jrose
parents: 20529
diff changeset
  1845
     * If, when the invoker is called, the supplied array argument does
b54a1f5cd35f 8001109: arity mismatch on a call to spreader method handle should elicit IllegalArgumentException
jrose
parents: 20529
diff changeset
  1846
     * not have the correct number of elements, the invoker will throw
b54a1f5cd35f 8001109: arity mismatch on a call to spreader method handle should elicit IllegalArgumentException
jrose
parents: 20529
diff changeset
  1847
     * an {@link IllegalArgumentException} instead of invoking the target.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1848
     * <p>
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1849
     * This method is equivalent to the following code (though it may be more efficient):
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1850
     * <blockquote><pre>{@code
9645
dabb5e4edc4c 7034977: JSR 292 MethodHandle.invokeGeneric should be renamed MethodHandle.invoke
jrose
parents: 8822
diff changeset
  1851
MethodHandle invoker = MethodHandles.invoker(type);
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1852
int spreadArgCount = type.parameterCount() - leadingArgCount;
8345
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1853
invoker = invoker.asSpreader(Object[].class, spreadArgCount);
9e2483e6cfab 7013417: JSR 292 needs to support variadic method handle calls
jrose
parents: 7562
diff changeset
  1854
return invoker;
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1855
     * }</pre></blockquote>
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1856
     * This method throws no reflective or security exceptions.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1857
     * @param type the desired target type
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1858
     * @param leadingArgCount number of fixed arguments, to be passed unchanged to the target
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1859
     * @return a method handle suitable for invoking any method handle of the given type
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1860
     * @throws NullPointerException if {@code type} is null
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1861
     * @throws IllegalArgumentException if {@code leadingArgCount} is not in
20529
b49b07206f7d 8019417: JSR 292 javadoc should clarify method handle arity limits
jrose
parents: 20528
diff changeset
  1862
     *                  the range from 0 to {@code type.parameterCount()} inclusive,
b49b07206f7d 8019417: JSR 292 javadoc should clarify method handle arity limits
jrose
parents: 20528
diff changeset
  1863
     *                  or if the resulting method handle's type would have
b49b07206f7d 8019417: JSR 292 javadoc should clarify method handle arity limits
jrose
parents: 20528
diff changeset
  1864
     *          <a href="MethodHandle.html#maxarity">too many parameters</a>
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1865
     */
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1866
    static public
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1867
    MethodHandle spreadInvoker(MethodType type, int leadingArgCount) {
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1868
        if (leadingArgCount < 0 || leadingArgCount > type.parameterCount())
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1869
            throw new IllegalArgumentException("bad argument count "+leadingArgCount);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1870
        return type.invokers().spreadInvoker(leadingArgCount);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1871
    }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1872
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1873
    /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1874
     * Produces a special <em>invoker method handle</em> which can be used to
9645
dabb5e4edc4c 7034977: JSR 292 MethodHandle.invokeGeneric should be renamed MethodHandle.invoke
jrose
parents: 8822
diff changeset
  1875
     * invoke any method handle of the given type, as if by {@link MethodHandle#invokeExact invokeExact}.
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1876
     * The resulting invoker will have a type which is
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1877
     * exactly equal to the desired type, except that it will accept
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1878
     * an additional leading argument of type {@code MethodHandle}.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1879
     * <p>
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  1880
     * This method is equivalent to the following code (though it may be more efficient):
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1881
     * {@code publicLookup().findVirtual(MethodHandle.class, "invokeExact", type)}
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1882
     *
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1883
     * <p style="font-size:smaller;">
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1884
     * <em>Discussion:</em>
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1885
     * Invoker method handles can be useful when working with variable method handles
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1886
     * of unknown types.
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1887
     * For example, to emulate an {@code invokeExact} call to a variable method
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1888
     * handle {@code M}, extract its type {@code T},
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1889
     * look up the invoker method {@code X} for {@code T},
9645
dabb5e4edc4c 7034977: JSR 292 MethodHandle.invokeGeneric should be renamed MethodHandle.invoke
jrose
parents: 8822
diff changeset
  1890
     * and call the invoker method, as {@code X.invoke(T, A...)}.
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1891
     * (It would not work to call {@code X.invokeExact}, since the type {@code T}
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1892
     * is unknown.)
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1893
     * If spreading, collecting, or other argument transformations are required,
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1894
     * they can be applied once to the invoker {@code X} and reused on many {@code M}
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1895
     * method handle values, as long as they are compatible with the type of {@code X}.
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1896
     * <p style="font-size:smaller;">
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1897
     * <em>(Note:  The invoker method is not available via the Core Reflection API.
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1898
     * An attempt to call {@linkplain java.lang.reflect.Method#invoke java.lang.reflect.Method.invoke}
9645
dabb5e4edc4c 7034977: JSR 292 MethodHandle.invokeGeneric should be renamed MethodHandle.invoke
jrose
parents: 8822
diff changeset
  1899
     * on the declared {@code invokeExact} or {@code invoke} method will raise an
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1900
     * {@link java.lang.UnsupportedOperationException UnsupportedOperationException}.)</em>
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1901
     * <p>
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1902
     * This method throws no reflective or security exceptions.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1903
     * @param type the desired target type
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1904
     * @return a method handle suitable for invoking any method handle of the given type
20529
b49b07206f7d 8019417: JSR 292 javadoc should clarify method handle arity limits
jrose
parents: 20528
diff changeset
  1905
     * @throws IllegalArgumentException if the resulting method handle's type would have
b49b07206f7d 8019417: JSR 292 javadoc should clarify method handle arity limits
jrose
parents: 20528
diff changeset
  1906
     *          <a href="MethodHandle.html#maxarity">too many parameters</a>
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1907
     */
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1908
    static public
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1909
    MethodHandle exactInvoker(MethodType type) {
8821
2836ee97ee27 6839872: remove implementation inheritance from JSR 292 APIs
jrose
parents: 8349
diff changeset
  1910
        return type.invokers().exactInvoker();
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1911
    }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1912
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1913
    /**
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1914
     * Produces a special <em>invoker method handle</em> which can be used to
9645
dabb5e4edc4c 7034977: JSR 292 MethodHandle.invokeGeneric should be renamed MethodHandle.invoke
jrose
parents: 8822
diff changeset
  1915
     * invoke any method handle compatible with the given type, as if by {@link MethodHandle#invoke invoke}.
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1916
     * The resulting invoker will have a type which is
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1917
     * exactly equal to the desired type, except that it will accept
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1918
     * an additional leading argument of type {@code MethodHandle}.
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1919
     * <p>
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1920
     * Before invoking its target, if the target differs from the expected type,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1921
     * the invoker will apply reference casts as
9645
dabb5e4edc4c 7034977: JSR 292 MethodHandle.invokeGeneric should be renamed MethodHandle.invoke
jrose
parents: 8822
diff changeset
  1922
     * necessary and box, unbox, or widen primitive values, as if by {@link MethodHandle#asType asType}.
dabb5e4edc4c 7034977: JSR 292 MethodHandle.invokeGeneric should be renamed MethodHandle.invoke
jrose
parents: 8822
diff changeset
  1923
     * Similarly, the return value will be converted as necessary.
dabb5e4edc4c 7034977: JSR 292 MethodHandle.invokeGeneric should be renamed MethodHandle.invoke
jrose
parents: 8822
diff changeset
  1924
     * If the target is a {@linkplain MethodHandle#asVarargsCollector variable arity method handle},
dabb5e4edc4c 7034977: JSR 292 MethodHandle.invokeGeneric should be renamed MethodHandle.invoke
jrose
parents: 8822
diff changeset
  1925
     * the required arity conversion will be made, again as if by {@link MethodHandle#asType asType}.
8346
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parents: 8345
diff changeset
  1926
     * <p>
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1927
     * This method is equivalent to the following code (though it may be more efficient):
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1928
     * {@code publicLookup().findVirtual(MethodHandle.class, "invoke", type)}
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1929
     * <p style="font-size:smaller;">
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1930
     * <em>Discussion:</em>
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1931
     * A {@linkplain MethodType#genericMethodType general method type} is one which
9752
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jrose
parents: 9731
diff changeset
  1932
     * mentions only {@code Object} arguments and return values.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1933
     * An invoker for such a type is capable of calling any method handle
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1934
     * of the same arity as the general type.
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1935
     * <p style="font-size:smaller;">
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1936
     * <em>(Note:  The invoker method is not available via the Core Reflection API.
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1937
     * An attempt to call {@linkplain java.lang.reflect.Method#invoke java.lang.reflect.Method.invoke}
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1938
     * on the declared {@code invokeExact} or {@code invoke} method will raise an
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  1939
     * {@link java.lang.UnsupportedOperationException UnsupportedOperationException}.)</em>
8346
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jrose
parents: 8345
diff changeset
  1940
     * <p>
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1941
     * This method throws no reflective or security exceptions.
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1942
     * @param type the desired target type
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1943
     * @return a method handle suitable for invoking any method handle convertible to the given type
20529
b49b07206f7d 8019417: JSR 292 javadoc should clarify method handle arity limits
jrose
parents: 20528
diff changeset
  1944
     * @throws IllegalArgumentException if the resulting method handle's type would have
b49b07206f7d 8019417: JSR 292 javadoc should clarify method handle arity limits
jrose
parents: 20528
diff changeset
  1945
     *          <a href="MethodHandle.html#maxarity">too many parameters</a>
8346
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jrose
parents: 8345
diff changeset
  1946
     */
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1947
    static public
9645
dabb5e4edc4c 7034977: JSR 292 MethodHandle.invokeGeneric should be renamed MethodHandle.invoke
jrose
parents: 8822
diff changeset
  1948
    MethodHandle invoker(MethodType type) {
dabb5e4edc4c 7034977: JSR 292 MethodHandle.invokeGeneric should be renamed MethodHandle.invoke
jrose
parents: 8822
diff changeset
  1949
        return type.invokers().generalInvoker();
dabb5e4edc4c 7034977: JSR 292 MethodHandle.invokeGeneric should be renamed MethodHandle.invoke
jrose
parents: 8822
diff changeset
  1950
    }
dabb5e4edc4c 7034977: JSR 292 MethodHandle.invokeGeneric should be renamed MethodHandle.invoke
jrose
parents: 8822
diff changeset
  1951
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1952
    static /*non-public*/
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1953
    MethodHandle basicInvoker(MethodType type) {
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1954
        return type.form().basicInvoker();
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
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parents:
diff changeset
  1955
    }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1956
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  1957
     /// method handle modification (creation from other method handles)
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1958
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  1959
    /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1960
     * Produces a method handle which adapts the type of the
9752
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jrose
parents: 9731
diff changeset
  1961
     * given method handle to a new type by pairwise argument and return type conversion.
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1962
     * The original type and new type must have the same number of arguments.
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1963
     * The resulting method handle is guaranteed to report a type
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1964
     * which is equal to the desired new type.
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1965
     * <p>
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1966
     * If the original type and new type are equal, returns target.
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1967
     * <p>
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1968
     * The same conversions are allowed as for {@link MethodHandle#asType MethodHandle.asType},
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1969
     * and some additional conversions are also applied if those conversions fail.
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1970
     * Given types <em>T0</em>, <em>T1</em>, one of the following conversions is applied
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1971
     * if possible, before or instead of any conversions done by {@code asType}:
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1972
     * <ul>
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1973
     * <li>If <em>T0</em> and <em>T1</em> are references, and <em>T1</em> is an interface type,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1974
     *     then the value of type <em>T0</em> is passed as a <em>T1</em> without a cast.
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1975
     *     (This treatment of interfaces follows the usage of the bytecode verifier.)
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1976
     * <li>If <em>T0</em> is boolean and <em>T1</em> is another primitive,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1977
     *     the boolean is converted to a byte value, 1 for true, 0 for false.
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1978
     *     (This treatment follows the usage of the bytecode verifier.)
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1979
     * <li>If <em>T1</em> is boolean and <em>T0</em> is another primitive,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1980
     *     <em>T0</em> is converted to byte via Java casting conversion (JLS 5.5),
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1981
     *     and the low order bit of the result is tested, as if by {@code (x & 1) != 0}.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1982
     * <li>If <em>T0</em> and <em>T1</em> are primitives other than boolean,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1983
     *     then a Java casting conversion (JLS 5.5) is applied.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1984
     *     (Specifically, <em>T0</em> will convert to <em>T1</em> by
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1985
     *     widening and/or narrowing.)
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1986
     * <li>If <em>T0</em> is a reference and <em>T1</em> a primitive, an unboxing
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1987
     *     conversion will be applied at runtime, possibly followed
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1988
     *     by a Java casting conversion (JLS 5.5) on the primitive value,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1989
     *     possibly followed by a conversion from byte to boolean by testing
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1990
     *     the low-order bit.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1991
     * <li>If <em>T0</em> is a reference and <em>T1</em> a primitive,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1992
     *     and if the reference is null at runtime, a zero value is introduced.
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1993
     * </ul>
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1994
     * @param target the method handle to invoke after arguments are retyped
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1995
     * @param newType the expected type of the new method handle
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  1996
     * @return a method handle which delegates to the target after performing
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1997
     *           any necessary argument conversions, and arranges for any
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  1998
     *           necessary return value conversions
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  1999
     * @throws NullPointerException if either argument is null
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2000
     * @throws WrongMethodTypeException if the conversion cannot be made
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2001
     * @see MethodHandle#asType
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2002
     */
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2003
    public static
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2004
    MethodHandle explicitCastArguments(MethodHandle target, MethodType newType) {
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2005
        if (!target.type().isCastableTo(newType)) {
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2006
            throw new WrongMethodTypeException("cannot explicitly cast "+target+" to "+newType);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2007
        }
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2008
        return MethodHandleImpl.makePairwiseConvert(target, newType, 2);
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2009
    }
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2010
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2011
    /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2012
     * Produces a method handle which adapts the calling sequence of the
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2013
     * given method handle to a new type, by reordering the arguments.
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2014
     * The resulting method handle is guaranteed to report a type
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2015
     * which is equal to the desired new type.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2016
     * <p>
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2017
     * The given array controls the reordering.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2018
     * Call {@code #I} the number of incoming parameters (the value
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2019
     * {@code newType.parameterCount()}, and call {@code #O} the number
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2020
     * of outgoing parameters (the value {@code target.type().parameterCount()}).
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2021
     * Then the length of the reordering array must be {@code #O},
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2022
     * and each element must be a non-negative number less than {@code #I}.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2023
     * For every {@code N} less than {@code #O}, the {@code N}-th
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2024
     * outgoing argument will be taken from the {@code I}-th incoming
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2025
     * argument, where {@code I} is {@code reorder[N]}.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2026
     * <p>
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2027
     * No argument or return value conversions are applied.
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2028
     * The type of each incoming argument, as determined by {@code newType},
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2029
     * must be identical to the type of the corresponding outgoing parameter
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2030
     * or parameters in the target method handle.
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2031
     * The return type of {@code newType} must be identical to the return
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2032
     * type of the original target.
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2033
     * <p>
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2034
     * The reordering array need not specify an actual permutation.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2035
     * An incoming argument will be duplicated if its index appears
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2036
     * more than once in the array, and an incoming argument will be dropped
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2037
     * if its index does not appear in the array.
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2038
     * As in the case of {@link #dropArguments(MethodHandle,int,List) dropArguments},
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2039
     * incoming arguments which are not mentioned in the reordering array
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2040
     * are may be any type, as determined only by {@code newType}.
18156
edb590d448c5 8016217: More javadoc warnings
alanb
parents: 16906
diff changeset
  2041
     * <blockquote><pre>{@code
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2042
import static java.lang.invoke.MethodHandles.*;
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2043
import static java.lang.invoke.MethodType.*;
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2044
...
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2045
MethodType intfn1 = methodType(int.class, int.class);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2046
MethodType intfn2 = methodType(int.class, int.class, int.class);
18569
0e46c17766b7 8019357: Fix doclint warnings in java.lang.invoke
darcy
parents: 18274
diff changeset
  2047
MethodHandle sub = ... (int x, int y) -> (x-y) ...;
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2048
assert(sub.type().equals(intfn2));
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2049
MethodHandle sub1 = permuteArguments(sub, intfn2, 0, 1);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2050
MethodHandle rsub = permuteArguments(sub, intfn2, 1, 0);
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2051
assert((int)rsub.invokeExact(1, 100) == 99);
18569
0e46c17766b7 8019357: Fix doclint warnings in java.lang.invoke
darcy
parents: 18274
diff changeset
  2052
MethodHandle add = ... (int x, int y) -> (x+y) ...;
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2053
assert(add.type().equals(intfn2));
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2054
MethodHandle twice = permuteArguments(add, intfn1, 0, 0);
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2055
assert(twice.type().equals(intfn1));
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2056
assert((int)twice.invokeExact(21) == 42);
18156
edb590d448c5 8016217: More javadoc warnings
alanb
parents: 16906
diff changeset
  2057
     * }</pre></blockquote>
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2058
     * @param target the method handle to invoke after arguments are reordered
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2059
     * @param newType the expected type of the new method handle
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2060
     * @param reorder an index array which controls the reordering
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2061
     * @return a method handle which delegates to the target after it
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2062
     *           drops unused arguments and moves and/or duplicates the other arguments
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2063
     * @throws NullPointerException if any argument is null
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2064
     * @throws IllegalArgumentException if the index array length is not equal to
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2065
     *                  the arity of the target, or if any index array element
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2066
     *                  not a valid index for a parameter of {@code newType},
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2067
     *                  or if two corresponding parameter types in
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2068
     *                  {@code target.type()} and {@code newType} are not identical,
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2069
     */
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2070
    public static
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2071
    MethodHandle permuteArguments(MethodHandle target, MethodType newType, int... reorder) {
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2072
        checkReorder(reorder, newType, target.type());
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2073
        return target.permuteArguments(newType, reorder);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2074
    }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2075
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2076
    private static void checkReorder(int[] reorder, MethodType newType, MethodType oldType) {
9646
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2077
        if (newType.returnType() != oldType.returnType())
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2078
            throw newIllegalArgumentException("return types do not match",
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2079
                    oldType, newType);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2080
        if (reorder.length == oldType.parameterCount()) {
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2081
            int limit = newType.parameterCount();
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2082
            boolean bad = false;
9646
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2083
            for (int j = 0; j < reorder.length; j++) {
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2084
                int i = reorder[j];
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2085
                if (i < 0 || i >= limit) {
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2086
                    bad = true; break;
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2087
                }
9646
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2088
                Class<?> src = newType.parameterType(i);
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2089
                Class<?> dst = oldType.parameterType(j);
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2090
                if (src != dst)
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2091
                    throw newIllegalArgumentException("parameter types do not match after reorder",
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2092
                            oldType, newType);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2093
            }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2094
            if (!bad)  return;
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2095
        }
9646
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2096
        throw newIllegalArgumentException("bad reorder array: "+Arrays.toString(reorder));
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2097
    }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2098
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2099
    /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2100
     * Produces a method handle of the requested return type which returns the given
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2101
     * constant value every time it is invoked.
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2102
     * <p>
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2103
     * Before the method handle is returned, the passed-in value is converted to the requested type.
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2104
     * If the requested type is primitive, widening primitive conversions are attempted,
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2105
     * else reference conversions are attempted.
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2106
     * <p>The returned method handle is equivalent to {@code identity(type).bindTo(value)}.
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2107
     * @param type the return type of the desired method handle
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2108
     * @param value the value to return
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2109
     * @return a method handle of the given return type and no arguments, which always returns the given value
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2110
     * @throws NullPointerException if the {@code type} argument is null
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2111
     * @throws ClassCastException if the value cannot be converted to the required return type
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2112
     * @throws IllegalArgumentException if the given type is {@code void.class}
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2113
     */
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2114
    public static
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2115
    MethodHandle constant(Class<?> type, Object value) {
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2116
        if (type.isPrimitive()) {
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2117
            if (type == void.class)
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2118
                throw newIllegalArgumentException("void type");
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2119
            Wrapper w = Wrapper.forPrimitiveType(type);
9646
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2120
            return insertArguments(identity(type), 0, w.convert(value, type));
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2121
        } else {
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2122
            return identity(type).bindTo(type.cast(value));
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2123
        }
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2124
    }
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2125
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2126
    /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2127
     * Produces a method handle which returns its sole argument when invoked.
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2128
     * @param type the type of the sole parameter and return value of the desired method handle
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2129
     * @return a unary method handle which accepts and returns the given type
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2130
     * @throws NullPointerException if the argument is null
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2131
     * @throws IllegalArgumentException if the given type is {@code void.class}
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2132
     */
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2133
    public static
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2134
    MethodHandle identity(Class<?> type) {
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2135
        if (type == void.class)
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2136
            throw newIllegalArgumentException("void type");
8821
2836ee97ee27 6839872: remove implementation inheritance from JSR 292 APIs
jrose
parents: 8349
diff changeset
  2137
        else if (type == Object.class)
2836ee97ee27 6839872: remove implementation inheritance from JSR 292 APIs
jrose
parents: 8349
diff changeset
  2138
            return ValueConversions.identity();
2836ee97ee27 6839872: remove implementation inheritance from JSR 292 APIs
jrose
parents: 8349
diff changeset
  2139
        else if (type.isPrimitive())
2836ee97ee27 6839872: remove implementation inheritance from JSR 292 APIs
jrose
parents: 8349
diff changeset
  2140
            return ValueConversions.identity(Wrapper.forPrimitiveType(type));
2836ee97ee27 6839872: remove implementation inheritance from JSR 292 APIs
jrose
parents: 8349
diff changeset
  2141
        else
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2142
            return MethodHandleImpl.makeReferenceIdentity(type);
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2143
    }
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2144
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2145
    /**
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2146
     * Provides a target method handle with one or more <em>bound arguments</em>
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2147
     * in advance of the method handle's invocation.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2148
     * The formal parameters to the target corresponding to the bound
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2149
     * arguments are called <em>bound parameters</em>.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2150
     * Returns a new method handle which saves away the bound arguments.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2151
     * When it is invoked, it receives arguments for any non-bound parameters,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2152
     * binds the saved arguments to their corresponding parameters,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2153
     * and calls the original target.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2154
     * <p>
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2155
     * The type of the new method handle will drop the types for the bound
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2156
     * parameters from the original target type, since the new method handle
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2157
     * will no longer require those arguments to be supplied by its callers.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2158
     * <p>
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2159
     * Each given argument object must match the corresponding bound parameter type.
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2160
     * If a bound parameter type is a primitive, the argument object
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2161
     * must be a wrapper, and will be unboxed to produce the primitive value.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2162
     * <p>
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2163
     * The {@code pos} argument selects which parameters are to be bound.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2164
     * It may range between zero and <i>N-L</i> (inclusively),
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2165
     * where <i>N</i> is the arity of the target method handle
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2166
     * and <i>L</i> is the length of the values array.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2167
     * @param target the method handle to invoke after the argument is inserted
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2168
     * @param pos where to insert the argument (zero for the first)
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2169
     * @param values the series of arguments to insert
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2170
     * @return a method handle which inserts an additional argument,
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2171
     *         before calling the original method handle
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2172
     * @throws NullPointerException if the target or the {@code values} array is null
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2173
     * @see MethodHandle#bindTo
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2174
     */
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2175
    public static
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2176
    MethodHandle insertArguments(MethodHandle target, int pos, Object... values) {
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2177
        int insCount = values.length;
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2178
        MethodType oldType = target.type();
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2179
        int outargs = oldType.parameterCount();
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2180
        int inargs  = outargs - insCount;
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2181
        if (inargs < 0)
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2182
            throw newIllegalArgumentException("too many values to insert");
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2183
        if (pos < 0 || pos > inargs)
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2184
            throw newIllegalArgumentException("no argument type to append");
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2185
        MethodHandle result = target;
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2186
        for (int i = 0; i < insCount; i++) {
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2187
            Object value = values[i];
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2188
            Class<?> ptype = oldType.parameterType(pos+i);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2189
            if (ptype.isPrimitive()) {
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2190
                char btype = 'I';
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2191
                Wrapper w = Wrapper.forPrimitiveType(ptype);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2192
                switch (w) {
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2193
                case LONG:    btype = 'J'; break;
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2194
                case FLOAT:   btype = 'F'; break;
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2195
                case DOUBLE:  btype = 'D'; break;
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2196
                }
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2197
                // perform unboxing and/or primitive conversion
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2198
                value = w.convert(value, ptype);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2199
                result = result.bindArgument(pos, btype, value);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2200
                continue;
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2201
            }
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2202
            value = ptype.cast(value);  // throw CCE if needed
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2203
            if (pos == 0) {
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2204
                result = result.bindReceiver(value);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2205
            } else {
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2206
                result = result.bindArgument(pos, 'L', value);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2207
            }
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2208
        }
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2209
        return result;
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2210
    }
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2211
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2212
    /**
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2213
     * Produces a method handle which will discard some dummy arguments
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2214
     * before calling some other specified <i>target</i> method handle.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2215
     * The type of the new method handle will be the same as the target's type,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2216
     * except it will also include the dummy argument types,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2217
     * at some given position.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2218
     * <p>
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2219
     * The {@code pos} argument may range between zero and <i>N</i>,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2220
     * where <i>N</i> is the arity of the target.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2221
     * If {@code pos} is zero, the dummy arguments will precede
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2222
     * the target's real arguments; if {@code pos} is <i>N</i>
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2223
     * they will come after.
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2224
     * <p>
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2225
     * <b>Example:</b>
20877
83ea903d5cf1 8026183: minor documentation problems in java.lang.invoke
rriggs
parents: 20853
diff changeset
  2226
     * <blockquote><pre>{@code
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2227
import static java.lang.invoke.MethodHandles.*;
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2228
import static java.lang.invoke.MethodType.*;
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2229
...
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2230
MethodHandle cat = lookup().findVirtual(String.class,
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2231
  "concat", methodType(String.class, String.class));
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2232
assertEquals("xy", (String) cat.invokeExact("x", "y"));
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2233
MethodType bigType = cat.type().insertParameterTypes(0, int.class, String.class);
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2234
MethodHandle d0 = dropArguments(cat, 0, bigType.parameterList().subList(0,2));
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2235
assertEquals(bigType, d0.type());
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2236
assertEquals("yz", (String) d0.invokeExact(123, "x", "y", "z"));
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2237
     * }</pre></blockquote>
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2238
     * <p>
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2239
     * This method is also equivalent to the following code:
20877
83ea903d5cf1 8026183: minor documentation problems in java.lang.invoke
rriggs
parents: 20853
diff changeset
  2240
     * <blockquote><pre>
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2241
     * {@link #dropArguments(MethodHandle,int,Class...) dropArguments}{@code (target, pos, valueTypes.toArray(new Class[0]))}
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2242
     * </pre></blockquote>
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2243
     * @param target the method handle to invoke after the arguments are dropped
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2244
     * @param valueTypes the type(s) of the argument(s) to drop
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2245
     * @param pos position of first argument to drop (zero for the leftmost)
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2246
     * @return a method handle which drops arguments of the given types,
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2247
     *         before calling the original method handle
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2248
     * @throws NullPointerException if the target is null,
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2249
     *                              or if the {@code valueTypes} list or any of its elements is null
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2250
     * @throws IllegalArgumentException if any element of {@code valueTypes} is {@code void.class},
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2251
     *                  or if {@code pos} is negative or greater than the arity of the target,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2252
     *                  or if the new method handle's type would have too many parameters
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2253
     */
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2254
    public static
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2255
    MethodHandle dropArguments(MethodHandle target, int pos, List<Class<?>> valueTypes) {
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2256
        MethodType oldType = target.type();  // get NPE
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2257
        int dropped = valueTypes.size();
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2258
        MethodType.checkSlotCount(dropped);
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2259
        if (dropped == 0)  return target;
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2260
        int outargs = oldType.parameterCount();
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2261
        int inargs  = outargs + dropped;
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2262
        if (pos < 0 || pos >= inargs)
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2263
            throw newIllegalArgumentException("no argument type to remove");
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2264
        ArrayList<Class<?>> ptypes = new ArrayList<>(oldType.parameterList());
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2265
        ptypes.addAll(pos, valueTypes);
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2266
        MethodType newType = MethodType.methodType(oldType.returnType(), ptypes);
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2267
        return target.dropArguments(newType, pos, dropped);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2268
    }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2269
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2270
    /**
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2271
     * Produces a method handle which will discard some dummy arguments
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2272
     * before calling some other specified <i>target</i> method handle.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2273
     * The type of the new method handle will be the same as the target's type,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2274
     * except it will also include the dummy argument types,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2275
     * at some given position.
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2276
     * <p>
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2277
     * The {@code pos} argument may range between zero and <i>N</i>,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2278
     * where <i>N</i> is the arity of the target.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2279
     * If {@code pos} is zero, the dummy arguments will precede
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2280
     * the target's real arguments; if {@code pos} is <i>N</i>
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2281
     * they will come after.
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2282
     * <p>
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2283
     * <b>Example:</b>
20877
83ea903d5cf1 8026183: minor documentation problems in java.lang.invoke
rriggs
parents: 20853
diff changeset
  2284
     * <blockquote><pre>{@code
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2285
import static java.lang.invoke.MethodHandles.*;
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2286
import static java.lang.invoke.MethodType.*;
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2287
...
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2288
MethodHandle cat = lookup().findVirtual(String.class,
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2289
  "concat", methodType(String.class, String.class));
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2290
assertEquals("xy", (String) cat.invokeExact("x", "y"));
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2291
MethodHandle d0 = dropArguments(cat, 0, String.class);
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2292
assertEquals("yz", (String) d0.invokeExact("x", "y", "z"));
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2293
MethodHandle d1 = dropArguments(cat, 1, String.class);
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2294
assertEquals("xz", (String) d1.invokeExact("x", "y", "z"));
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2295
MethodHandle d2 = dropArguments(cat, 2, String.class);
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2296
assertEquals("xy", (String) d2.invokeExact("x", "y", "z"));
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2297
MethodHandle d12 = dropArguments(cat, 1, int.class, boolean.class);
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2298
assertEquals("xz", (String) d12.invokeExact("x", 12, true, "z"));
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2299
     * }</pre></blockquote>
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2300
     * <p>
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2301
     * This method is also equivalent to the following code:
20877
83ea903d5cf1 8026183: minor documentation problems in java.lang.invoke
rriggs
parents: 20853
diff changeset
  2302
     * <blockquote><pre>
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2303
     * {@link #dropArguments(MethodHandle,int,List) dropArguments}{@code (target, pos, Arrays.asList(valueTypes))}
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2304
     * </pre></blockquote>
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2305
     * @param target the method handle to invoke after the arguments are dropped
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2306
     * @param valueTypes the type(s) of the argument(s) to drop
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2307
     * @param pos position of first argument to drop (zero for the leftmost)
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2308
     * @return a method handle which drops arguments of the given types,
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2309
     *         before calling the original method handle
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2310
     * @throws NullPointerException if the target is null,
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2311
     *                              or if the {@code valueTypes} array or any of its elements is null
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2312
     * @throws IllegalArgumentException if any element of {@code valueTypes} is {@code void.class},
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2313
     *                  or if {@code pos} is negative or greater than the arity of the target,
20529
b49b07206f7d 8019417: JSR 292 javadoc should clarify method handle arity limits
jrose
parents: 20528
diff changeset
  2314
     *                  or if the new method handle's type would have
b49b07206f7d 8019417: JSR 292 javadoc should clarify method handle arity limits
jrose
parents: 20528
diff changeset
  2315
     *                  <a href="MethodHandle.html#maxarity">too many parameters</a>
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2316
     */
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2317
    public static
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2318
    MethodHandle dropArguments(MethodHandle target, int pos, Class<?>... valueTypes) {
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2319
        return dropArguments(target, pos, Arrays.asList(valueTypes));
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2320
    }
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2321
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2322
    /**
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2323
     * Adapts a target method handle by pre-processing
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2324
     * one or more of its arguments, each with its own unary filter function,
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2325
     * and then calling the target with each pre-processed argument
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2326
     * replaced by the result of its corresponding filter function.
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2327
     * <p>
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2328
     * The pre-processing is performed by one or more method handles,
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2329
     * specified in the elements of the {@code filters} array.
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2330
     * The first element of the filter array corresponds to the {@code pos}
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2331
     * argument of the target, and so on in sequence.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2332
     * <p>
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2333
     * Null arguments in the array are treated as identity functions,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2334
     * and the corresponding arguments left unchanged.
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2335
     * (If there are no non-null elements in the array, the original target is returned.)
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2336
     * Each filter is applied to the corresponding argument of the adapter.
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2337
     * <p>
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2338
     * If a filter {@code F} applies to the {@code N}th argument of
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2339
     * the target, then {@code F} must be a method handle which
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2340
     * takes exactly one argument.  The type of {@code F}'s sole argument
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2341
     * replaces the corresponding argument type of the target
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2342
     * in the resulting adapted method handle.
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2343
     * The return type of {@code F} must be identical to the corresponding
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2344
     * parameter type of the target.
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2345
     * <p>
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2346
     * It is an error if there are elements of {@code filters}
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2347
     * (null or not)
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2348
     * which do not correspond to argument positions in the target.
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2349
     * <p><b>Example:</b>
20877
83ea903d5cf1 8026183: minor documentation problems in java.lang.invoke
rriggs
parents: 20853
diff changeset
  2350
     * <blockquote><pre>{@code
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2351
import static java.lang.invoke.MethodHandles.*;
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2352
import static java.lang.invoke.MethodType.*;
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2353
...
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2354
MethodHandle cat = lookup().findVirtual(String.class,
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2355
  "concat", methodType(String.class, String.class));
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2356
MethodHandle upcase = lookup().findVirtual(String.class,
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2357
  "toUpperCase", methodType(String.class));
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2358
assertEquals("xy", (String) cat.invokeExact("x", "y"));
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2359
MethodHandle f0 = filterArguments(cat, 0, upcase);
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2360
assertEquals("Xy", (String) f0.invokeExact("x", "y")); // Xy
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2361
MethodHandle f1 = filterArguments(cat, 1, upcase);
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2362
assertEquals("xY", (String) f1.invokeExact("x", "y")); // xY
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2363
MethodHandle f2 = filterArguments(cat, 0, upcase, upcase);
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2364
assertEquals("XY", (String) f2.invokeExact("x", "y")); // XY
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2365
     * }</pre></blockquote>
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2366
     * <p> Here is pseudocode for the resulting adapter:
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2367
     * <blockquote><pre>{@code
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2368
     * V target(P... p, A[i]... a[i], B... b);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2369
     * A[i] filter[i](V[i]);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2370
     * T adapter(P... p, V[i]... v[i], B... b) {
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2371
     *   return target(p..., f[i](v[i])..., b...);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2372
     * }
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2373
     * }</pre></blockquote>
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2374
     *
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2375
     * @param target the method handle to invoke after arguments are filtered
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2376
     * @param pos the position of the first argument to filter
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2377
     * @param filters method handles to call initially on filtered arguments
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2378
     * @return method handle which incorporates the specified argument filtering logic
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2379
     * @throws NullPointerException if the target is null
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2380
     *                              or if the {@code filters} array is null
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2381
     * @throws IllegalArgumentException if a non-null element of {@code filters}
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2382
     *          does not match a corresponding argument type of target as described above,
20529
b49b07206f7d 8019417: JSR 292 javadoc should clarify method handle arity limits
jrose
parents: 20528
diff changeset
  2383
     *          or if the {@code pos+filters.length} is greater than {@code target.type().parameterCount()},
b49b07206f7d 8019417: JSR 292 javadoc should clarify method handle arity limits
jrose
parents: 20528
diff changeset
  2384
     *          or if the resulting method handle's type would have
b49b07206f7d 8019417: JSR 292 javadoc should clarify method handle arity limits
jrose
parents: 20528
diff changeset
  2385
     *          <a href="MethodHandle.html#maxarity">too many parameters</a>
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2386
     */
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2387
    public static
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2388
    MethodHandle filterArguments(MethodHandle target, int pos, MethodHandle... filters) {
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2389
        MethodType targetType = target.type();
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2390
        MethodHandle adapter = target;
9646
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2391
        MethodType adapterType = null;
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2392
        assert((adapterType = targetType) != null);
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2393
        int maxPos = targetType.parameterCount();
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2394
        if (pos + filters.length > maxPos)
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2395
            throw newIllegalArgumentException("too many filters");
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2396
        int curPos = pos-1;  // pre-incremented
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2397
        for (MethodHandle filter : filters) {
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2398
            curPos += 1;
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2399
            if (filter == null)  continue;  // ignore null elements of filters
9646
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2400
            adapter = filterArgument(adapter, curPos, filter);
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2401
            assert((adapterType = adapterType.changeParameterType(curPos, filter.type().parameterType(0))) != null);
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2402
        }
9646
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2403
        assert(adapterType.equals(adapter.type()));
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2404
        return adapter;
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2405
    }
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2406
9646
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2407
    /*non-public*/ static
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2408
    MethodHandle filterArgument(MethodHandle target, int pos, MethodHandle filter) {
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2409
        MethodType targetType = target.type();
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2410
        MethodType filterType = filter.type();
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2411
        if (filterType.parameterCount() != 1
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2412
            || filterType.returnType() != targetType.parameterType(pos))
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2413
            throw newIllegalArgumentException("target and filter types do not match", targetType, filterType);
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2414
        return MethodHandleImpl.makeCollectArguments(target, filter, pos, false);
9646
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2415
    }
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2416
20533
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2417
    /**
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2418
     * Adapts a target method handle by pre-processing
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2419
     * a sub-sequence of its arguments with a filter (another method handle).
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2420
     * The pre-processed arguments are replaced by the result (if any) of the
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2421
     * filter function.
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2422
     * The target is then called on the modified (usually shortened) argument list.
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2423
     * <p>
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2424
     * If the filter returns a value, the target must accept that value as
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2425
     * its argument in position {@code pos}, preceded and/or followed by
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2426
     * any arguments not passed to the filter.
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2427
     * If the filter returns void, the target must accept all arguments
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2428
     * not passed to the filter.
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2429
     * No arguments are reordered, and a result returned from the filter
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2430
     * replaces (in order) the whole subsequence of arguments originally
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2431
     * passed to the adapter.
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2432
     * <p>
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2433
     * The argument types (if any) of the filter
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2434
     * replace zero or one argument types of the target, at position {@code pos},
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2435
     * in the resulting adapted method handle.
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2436
     * The return type of the filter (if any) must be identical to the
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2437
     * argument type of the target at position {@code pos}, and that target argument
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2438
     * is supplied by the return value of the filter.
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2439
     * <p>
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2440
     * In all cases, {@code pos} must be greater than or equal to zero, and
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2441
     * {@code pos} must also be less than or equal to the target's arity.
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2442
     * <p><b>Example:</b>
20877
83ea903d5cf1 8026183: minor documentation problems in java.lang.invoke
rriggs
parents: 20853
diff changeset
  2443
     * <blockquote><pre>{@code
20533
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2444
import static java.lang.invoke.MethodHandles.*;
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2445
import static java.lang.invoke.MethodType.*;
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2446
...
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2447
MethodHandle deepToString = publicLookup()
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2448
  .findStatic(Arrays.class, "deepToString", methodType(String.class, Object[].class));
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2449
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2450
MethodHandle ts1 = deepToString.asCollector(String[].class, 1);
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2451
assertEquals("[strange]", (String) ts1.invokeExact("strange"));
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2452
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2453
MethodHandle ts2 = deepToString.asCollector(String[].class, 2);
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2454
assertEquals("[up, down]", (String) ts2.invokeExact("up", "down"));
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2455
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2456
MethodHandle ts3 = deepToString.asCollector(String[].class, 3);
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2457
MethodHandle ts3_ts2 = collectArguments(ts3, 1, ts2);
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2458
assertEquals("[top, [up, down], strange]",
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2459
             (String) ts3_ts2.invokeExact("top", "up", "down", "strange"));
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2460
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2461
MethodHandle ts3_ts2_ts1 = collectArguments(ts3_ts2, 3, ts1);
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2462
assertEquals("[top, [up, down], [strange]]",
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2463
             (String) ts3_ts2_ts1.invokeExact("top", "up", "down", "strange"));
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2464
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2465
MethodHandle ts3_ts2_ts3 = collectArguments(ts3_ts2, 1, ts3);
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2466
assertEquals("[top, [[up, down, strange], charm], bottom]",
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2467
             (String) ts3_ts2_ts3.invokeExact("top", "up", "down", "strange", "charm", "bottom"));
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2468
     * }</pre></blockquote>
20533
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2469
     * <p> Here is pseudocode for the resulting adapter:
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2470
     * <blockquote><pre>{@code
20533
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2471
     * T target(A...,V,C...);
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2472
     * V filter(B...);
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2473
     * T adapter(A... a,B... b,C... c) {
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2474
     *   V v = filter(b...);
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2475
     *   return target(a...,v,c...);
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2476
     * }
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2477
     * // and if the filter has no arguments:
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2478
     * T target2(A...,V,C...);
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2479
     * V filter2();
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2480
     * T adapter2(A... a,C... c) {
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2481
     *   V v = filter2();
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2482
     *   return target2(a...,v,c...);
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2483
     * }
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2484
     * // and if the filter has a void return:
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2485
     * T target3(A...,C...);
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2486
     * void filter3(B...);
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2487
     * void adapter3(A... a,B... b,C... c) {
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2488
     *   filter3(b...);
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2489
     *   return target3(a...,c...);
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2490
     * }
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2491
     * }</pre></blockquote>
20533
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2492
     * <p>
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2493
     * A collection adapter {@code collectArguments(mh, 0, coll)} is equivalent to
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2494
     * one which first "folds" the affected arguments, and then drops them, in separate
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2495
     * steps as follows:
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2496
     * <blockquote><pre>{@code
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2497
     * mh = MethodHandles.dropArguments(mh, 1, coll.type().parameterList()); //step 2
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2498
     * mh = MethodHandles.foldArguments(mh, coll); //step 1
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2499
     * }</pre></blockquote>
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2500
     * If the target method handle consumes no arguments besides than the result
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2501
     * (if any) of the filter {@code coll}, then {@code collectArguments(mh, 0, coll)}
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2502
     * is equivalent to {@code filterReturnValue(coll, mh)}.
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2503
     * If the filter method handle {@code coll} consumes one argument and produces
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2504
     * a non-void result, then {@code collectArguments(mh, N, coll)}
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2505
     * is equivalent to {@code filterArguments(mh, N, coll)}.
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2506
     * Other equivalences are possible but would require argument permutation.
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2507
     *
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2508
     * @param target the method handle to invoke after filtering the subsequence of arguments
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2509
     * @param pos the position of the first adapter argument to pass to the filter,
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2510
     *            and/or the target argument which receives the result of the filter
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2511
     * @param filter method handle to call on the subsequence of arguments
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2512
     * @return method handle which incorporates the specified argument subsequence filtering logic
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2513
     * @throws NullPointerException if either argument is null
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2514
     * @throws IllegalArgumentException if the return type of {@code filter}
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2515
     *          is non-void and is not the same as the {@code pos} argument of the target,
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2516
     *          or if {@code pos} is not between 0 and the target's arity, inclusive,
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2517
     *          or if the resulting method handle's type would have
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2518
     *          <a href="MethodHandle.html#maxarity">too many parameters</a>
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2519
     * @see MethodHandles#foldArguments
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2520
     * @see MethodHandles#filterArguments
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2521
     * @see MethodHandles#filterReturnValue
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2522
     */
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2523
    public static
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2524
    MethodHandle collectArguments(MethodHandle target, int pos, MethodHandle filter) {
13610
28122b96858e 7191102: nightly failures after JSR 292 lazy method handle update (round 3)
jrose
parents: 13423
diff changeset
  2525
        MethodType targetType = target.type();
20533
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2526
        MethodType filterType = filter.type();
13610
28122b96858e 7191102: nightly failures after JSR 292 lazy method handle update (round 3)
jrose
parents: 13423
diff changeset
  2527
        if (filterType.returnType() != void.class &&
28122b96858e 7191102: nightly failures after JSR 292 lazy method handle update (round 3)
jrose
parents: 13423
diff changeset
  2528
            filterType.returnType() != targetType.parameterType(pos))
28122b96858e 7191102: nightly failures after JSR 292 lazy method handle update (round 3)
jrose
parents: 13423
diff changeset
  2529
            throw newIllegalArgumentException("target and filter types do not match", targetType, filterType);
20533
bee974bc42ac 8001110: method handles should have a collectArguments transform, generalizing asCollector
jrose
parents: 20532
diff changeset
  2530
        return MethodHandleImpl.makeCollectArguments(target, filter, pos, false);
13610
28122b96858e 7191102: nightly failures after JSR 292 lazy method handle update (round 3)
jrose
parents: 13423
diff changeset
  2531
    }
28122b96858e 7191102: nightly failures after JSR 292 lazy method handle update (round 3)
jrose
parents: 13423
diff changeset
  2532
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2533
    /**
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2534
     * Adapts a target method handle by post-processing
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2535
     * its return value (if any) with a filter (another method handle).
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2536
     * The result of the filter is returned from the adapter.
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2537
     * <p>
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2538
     * If the target returns a value, the filter must accept that value as
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2539
     * its only argument.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2540
     * If the target returns void, the filter must accept no arguments.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2541
     * <p>
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2542
     * The return type of the filter
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2543
     * replaces the return type of the target
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2544
     * in the resulting adapted method handle.
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2545
     * The argument type of the filter (if any) must be identical to the
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2546
     * return type of the target.
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2547
     * <p><b>Example:</b>
20877
83ea903d5cf1 8026183: minor documentation problems in java.lang.invoke
rriggs
parents: 20853
diff changeset
  2548
     * <blockquote><pre>{@code
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2549
import static java.lang.invoke.MethodHandles.*;
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2550
import static java.lang.invoke.MethodType.*;
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2551
...
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2552
MethodHandle cat = lookup().findVirtual(String.class,
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2553
  "concat", methodType(String.class, String.class));
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2554
MethodHandle length = lookup().findVirtual(String.class,
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2555
  "length", methodType(int.class));
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2556
System.out.println((String) cat.invokeExact("x", "y")); // xy
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2557
MethodHandle f0 = filterReturnValue(cat, length);
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2558
System.out.println((int) f0.invokeExact("x", "y")); // 2
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2559
     * }</pre></blockquote>
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2560
     * <p> Here is pseudocode for the resulting adapter:
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2561
     * <blockquote><pre>{@code
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2562
     * V target(A...);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2563
     * T filter(V);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2564
     * T adapter(A... a) {
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2565
     *   V v = target(a...);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2566
     *   return filter(v);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2567
     * }
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2568
     * // and if the target has a void return:
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2569
     * void target2(A...);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2570
     * T filter2();
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2571
     * T adapter2(A... a) {
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2572
     *   target2(a...);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2573
     *   return filter2();
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2574
     * }
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2575
     * // and if the filter has a void return:
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2576
     * V target3(A...);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2577
     * void filter3(V);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2578
     * void adapter3(A... a) {
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2579
     *   V v = target3(a...);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2580
     *   filter3(v);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2581
     * }
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2582
     * }</pre></blockquote>
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2583
     * @param target the method handle to invoke before filtering the return value
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2584
     * @param filter method handle to call on the return value
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2585
     * @return method handle which incorporates the specified return value filtering logic
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2586
     * @throws NullPointerException if either argument is null
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2587
     * @throws IllegalArgumentException if the argument list of {@code filter}
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2588
     *          does not match the return type of target as described above
7554
8a0ad9757002 6939224: MethodHandle.invokeGeneric needs to perform the correct set of conversions
jrose
parents: 7053
diff changeset
  2589
     */
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2590
    public static
7554
8a0ad9757002 6939224: MethodHandle.invokeGeneric needs to perform the correct set of conversions
jrose
parents: 7053
diff changeset
  2591
    MethodHandle filterReturnValue(MethodHandle target, MethodHandle filter) {
8a0ad9757002 6939224: MethodHandle.invokeGeneric needs to perform the correct set of conversions
jrose
parents: 7053
diff changeset
  2592
        MethodType targetType = target.type();
8a0ad9757002 6939224: MethodHandle.invokeGeneric needs to perform the correct set of conversions
jrose
parents: 7053
diff changeset
  2593
        MethodType filterType = filter.type();
9646
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2594
        Class<?> rtype = targetType.returnType();
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2595
        int filterValues = filterType.parameterCount();
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2596
        if (filterValues == 0
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2597
                ? (rtype != void.class)
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2598
                : (rtype != filterType.parameterType(0)))
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2599
            throw newIllegalArgumentException("target and filter types do not match", target, filter);
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2600
        // result = fold( lambda(retval, arg...) { filter(retval) },
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2601
        //                lambda(        arg...) { target(arg...) } )
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2602
        return MethodHandleImpl.makeCollectArguments(filter, target, 0, false);
7554
8a0ad9757002 6939224: MethodHandle.invokeGeneric needs to perform the correct set of conversions
jrose
parents: 7053
diff changeset
  2603
    }
8a0ad9757002 6939224: MethodHandle.invokeGeneric needs to perform the correct set of conversions
jrose
parents: 7053
diff changeset
  2604
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2605
    /**
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2606
     * Adapts a target method handle by pre-processing
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2607
     * some of its arguments, and then calling the target with
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2608
     * the result of the pre-processing, inserted into the original
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2609
     * sequence of arguments.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2610
     * <p>
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2611
     * The pre-processing is performed by {@code combiner}, a second method handle.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2612
     * Of the arguments passed to the adapter, the first {@code N} arguments
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2613
     * are copied to the combiner, which is then called.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2614
     * (Here, {@code N} is defined as the parameter count of the combiner.)
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2615
     * After this, control passes to the target, with any result
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2616
     * from the combiner inserted before the original {@code N} incoming
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2617
     * arguments.
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2618
     * <p>
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2619
     * If the combiner returns a value, the first parameter type of the target
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2620
     * must be identical with the return type of the combiner, and the next
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2621
     * {@code N} parameter types of the target must exactly match the parameters
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2622
     * of the combiner.
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2623
     * <p>
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2624
     * If the combiner has a void return, no result will be inserted,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2625
     * and the first {@code N} parameter types of the target
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2626
     * must exactly match the parameters of the combiner.
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2627
     * <p>
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2628
     * The resulting adapter is the same type as the target, except that the
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2629
     * first parameter type is dropped,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2630
     * if it corresponds to the result of the combiner.
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2631
     * <p>
7555
a279ebc3b25c 6981777: implement JSR 292 EG adjustments from summer 2010
jrose
parents: 7554
diff changeset
  2632
     * (Note that {@link #dropArguments(MethodHandle,int,List) dropArguments} can be used to remove any arguments
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2633
     * that either the combiner or the target does not wish to receive.
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2634
     * If some of the incoming arguments are destined only for the combiner,
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2635
     * consider using {@link MethodHandle#asCollector asCollector} instead, since those
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2636
     * arguments will not need to be live on the stack on entry to the
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2637
     * target.)
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2638
     * <p><b>Example:</b>
20877
83ea903d5cf1 8026183: minor documentation problems in java.lang.invoke
rriggs
parents: 20853
diff changeset
  2639
     * <blockquote><pre>{@code
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2640
import static java.lang.invoke.MethodHandles.*;
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2641
import static java.lang.invoke.MethodType.*;
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2642
...
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2643
MethodHandle trace = publicLookup().findVirtual(java.io.PrintStream.class,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2644
  "println", methodType(void.class, String.class))
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2645
    .bindTo(System.out);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2646
MethodHandle cat = lookup().findVirtual(String.class,
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2647
  "concat", methodType(String.class, String.class));
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2648
assertEquals("boojum", (String) cat.invokeExact("boo", "jum"));
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2649
MethodHandle catTrace = foldArguments(cat, trace);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2650
// also prints "boo":
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2651
assertEquals("boojum", (String) catTrace.invokeExact("boo", "jum"));
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2652
     * }</pre></blockquote>
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2653
     * <p> Here is pseudocode for the resulting adapter:
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2654
     * <blockquote><pre>{@code
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2655
     * // there are N arguments in A...
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2656
     * T target(V, A[N]..., B...);
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2657
     * V combiner(A...);
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2658
     * T adapter(A... a, B... b) {
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2659
     *   V v = combiner(a...);
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2660
     *   return target(v, a..., b...);
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2661
     * }
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2662
     * // and if the combiner has a void return:
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2663
     * T target2(A[N]..., B...);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2664
     * void combiner2(A...);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2665
     * T adapter2(A... a, B... b) {
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2666
     *   combiner2(a...);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2667
     *   return target2(a..., b...);
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2668
     * }
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2669
     * }</pre></blockquote>
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2670
     * @param target the method handle to invoke after arguments are combined
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2671
     * @param combiner method handle to call initially on the incoming arguments
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2672
     * @return method handle which incorporates the specified argument folding logic
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2673
     * @throws NullPointerException if either argument is null
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2674
     * @throws IllegalArgumentException if {@code combiner}'s return type
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2675
     *          is non-void and not the same as the first argument type of
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2676
     *          the target, or if the initial {@code N} argument types
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2677
     *          of the target
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2678
     *          (skipping one matching the {@code combiner}'s return type)
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2679
     *          are not identical with the argument types of {@code combiner}
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2680
     */
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2681
    public static
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2682
    MethodHandle foldArguments(MethodHandle target, MethodHandle combiner) {
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2683
        int pos = 0;
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2684
        MethodType targetType = target.type();
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2685
        MethodType combinerType = combiner.type();
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2686
        int foldPos = pos;
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2687
        int foldArgs = combinerType.parameterCount();
9646
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2688
        int foldVals = combinerType.returnType() == void.class ? 0 : 1;
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2689
        int afterInsertPos = foldPos + foldVals;
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2690
        boolean ok = (targetType.parameterCount() >= afterInsertPos + foldArgs);
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2691
        if (ok && !(combinerType.parameterList()
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2692
                    .equals(targetType.parameterList().subList(afterInsertPos,
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2693
                                                               afterInsertPos + foldArgs))))
7554
8a0ad9757002 6939224: MethodHandle.invokeGeneric needs to perform the correct set of conversions
jrose
parents: 7053
diff changeset
  2694
            ok = false;
9646
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2695
        if (ok && foldVals != 0 && !combinerType.returnType().equals(targetType.parameterType(0)))
7554
8a0ad9757002 6939224: MethodHandle.invokeGeneric needs to perform the correct set of conversions
jrose
parents: 7053
diff changeset
  2696
            ok = false;
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2697
        if (!ok)
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2698
            throw misMatchedTypes("target and combiner types", targetType, combinerType);
9646
5ebbe5ab084f 6939861: JVM should handle more conversion operations
jrose
parents: 9645
diff changeset
  2699
        MethodType newType = targetType.dropParameterTypes(foldPos, afterInsertPos);
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2700
        return MethodHandleImpl.makeCollectArguments(target, combiner, foldPos, true);
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2701
    }
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2702
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2703
    /**
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2704
     * Makes a method handle which adapts a target method handle,
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2705
     * by guarding it with a test, a boolean-valued method handle.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2706
     * If the guard fails, a fallback handle is called instead.
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2707
     * All three method handles must have the same corresponding
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2708
     * argument and return types, except that the return type
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2709
     * of the test must be boolean, and the test is allowed
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2710
     * to have fewer arguments than the other two method handles.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2711
     * <p> Here is pseudocode for the resulting adapter:
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2712
     * <blockquote><pre>{@code
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2713
     * boolean test(A...);
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2714
     * T target(A...,B...);
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2715
     * T fallback(A...,B...);
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2716
     * T adapter(A... a,B... b) {
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2717
     *   if (test(a...))
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2718
     *     return target(a..., b...);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2719
     *   else
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2720
     *     return fallback(a..., b...);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2721
     * }
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2722
     * }</pre></blockquote>
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2723
     * Note that the test arguments ({@code a...} in the pseudocode) cannot
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2724
     * be modified by execution of the test, and so are passed unchanged
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2725
     * from the caller to the target or fallback as appropriate.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2726
     * @param test method handle used for test, must return boolean
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2727
     * @param target method handle to call if test passes
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2728
     * @param fallback method handle to call if test fails
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2729
     * @return method handle which incorporates the specified if/then/else logic
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2730
     * @throws NullPointerException if any argument is null
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2731
     * @throws IllegalArgumentException if {@code test} does not return boolean,
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2732
     *          or if all three method types do not match (with the return
9752
88ab34b6da6d 7032323: code changes for JSR 292 EG adjustments to API, through Public Review
jrose
parents: 9731
diff changeset
  2733
     *          type of {@code test} changed to match that of the target).
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2734
     */
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2735
    public static
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2736
    MethodHandle guardWithTest(MethodHandle test,
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2737
                               MethodHandle target,
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2738
                               MethodHandle fallback) {
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2739
        MethodType gtype = test.type();
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2740
        MethodType ttype = target.type();
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2741
        MethodType ftype = fallback.type();
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2742
        if (!ttype.equals(ftype))
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2743
            throw misMatchedTypes("target and fallback types", ttype, ftype);
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2744
        if (gtype.returnType() != boolean.class)
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2745
            throw newIllegalArgumentException("guard type is not a predicate "+gtype);
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2746
        List<Class<?>> targs = ttype.parameterList();
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2747
        List<Class<?>> gargs = gtype.parameterList();
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2748
        if (!targs.equals(gargs)) {
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2749
            int gpc = gargs.size(), tpc = targs.size();
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2750
            if (gpc >= tpc || !targs.subList(0, gpc).equals(gargs))
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2751
                throw misMatchedTypes("target and test types", ttype, gtype);
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2752
            test = dropArguments(test, gpc, targs.subList(gpc, tpc));
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2753
            gtype = test.type();
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2754
        }
8821
2836ee97ee27 6839872: remove implementation inheritance from JSR 292 APIs
jrose
parents: 8349
diff changeset
  2755
        return MethodHandleImpl.makeGuardWithTest(test, target, fallback);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2756
    }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2757
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2758
    static RuntimeException misMatchedTypes(String what, MethodType t1, MethodType t2) {
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2759
        return newIllegalArgumentException(what + " must match: " + t1 + " != " + t2);
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2760
    }
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2761
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2762
    /**
8822
8145ab9f5f86 7012648: move JSR 292 to package java.lang.invoke and adjust names
jrose
parents: 8821
diff changeset
  2763
     * Makes a method handle which adapts a target method handle,
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2764
     * by running it inside an exception handler.
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2765
     * If the target returns normally, the adapter returns that value.
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2766
     * If an exception matching the specified type is thrown, the fallback
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2767
     * handle is called instead on the exception, plus the original arguments.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2768
     * <p>
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2769
     * The target and handler must have the same corresponding
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2770
     * argument and return types, except that handler may omit trailing arguments
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2771
     * (similarly to the predicate in {@link #guardWithTest guardWithTest}).
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2772
     * Also, the handler must have an extra leading parameter of {@code exType} or a supertype.
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2773
     * <p> Here is pseudocode for the resulting adapter:
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2774
     * <blockquote><pre>{@code
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2775
     * T target(A..., B...);
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2776
     * T handler(ExType, A...);
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2777
     * T adapter(A... a, B... b) {
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2778
     *   try {
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2779
     *     return target(a..., b...);
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2780
     *   } catch (ExType ex) {
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2781
     *     return handler(ex, a...);
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2782
     *   }
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2783
     * }
20535
cc85c8626435 8024438: JSR 292 API specification maintenance for JDK 8
jrose
parents: 20534
diff changeset
  2784
     * }</pre></blockquote>
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2785
     * Note that the saved arguments ({@code a...} in the pseudocode) cannot
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2786
     * be modified by execution of the target, and so are passed unchanged
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2787
     * from the caller to the handler, if the handler is invoked.
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2788
     * <p>
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2789
     * The target and handler must return the same type, even if the handler
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2790
     * always throws.  (This might happen, for instance, because the handler
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2791
     * is simulating a {@code finally} clause).
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2792
     * To create such a throwing handler, compose the handler creation logic
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2793
     * with {@link #throwException throwException},
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2794
     * in order to create a method handle of the correct return type.
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2795
     * @param target method handle to call
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2796
     * @param exType the type of exception which the handler will catch
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2797
     * @param handler method handle to call if a matching exception is thrown
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2798
     * @return method handle which incorporates the specified try/catch logic
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2799
     * @throws NullPointerException if any argument is null
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2800
     * @throws IllegalArgumentException if {@code handler} does not accept
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2801
     *          the given exception type, or if the method handle types do
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2802
     *          not match in their return types and their
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2803
     *          corresponding parameters
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2804
     */
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2805
    public static
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2806
    MethodHandle catchException(MethodHandle target,
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2807
                                Class<? extends Throwable> exType,
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2808
                                MethodHandle handler) {
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2809
        MethodType ttype = target.type();
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2810
        MethodType htype = handler.type();
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2811
        if (htype.parameterCount() < 1 ||
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2812
            !htype.parameterType(0).isAssignableFrom(exType))
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2813
            throw newIllegalArgumentException("handler does not accept exception type "+exType);
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2814
        if (htype.returnType() != ttype.returnType())
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2815
            throw misMatchedTypes("target and handler return types", ttype, htype);
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2816
        List<Class<?>> targs = ttype.parameterList();
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2817
        List<Class<?>> hargs = htype.parameterList();
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2818
        hargs = hargs.subList(1, hargs.size());  // omit leading parameter from handler
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2819
        if (!targs.equals(hargs)) {
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2820
            int hpc = hargs.size(), tpc = targs.size();
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2821
            if (hpc >= tpc || !targs.subList(0, hpc).equals(hargs))
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2822
                throw misMatchedTypes("target and handler types", ttype, htype);
9730
e4b334d47f4b 7032850: MethodHandle.invokeGeneric throws unspecified RuntimeException if parameterized method is called
jrose
parents: 9646
diff changeset
  2823
            handler = dropArguments(handler, 1+hpc, targs.subList(hpc, tpc));
7562
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2824
            htype = handler.type();
a0ad195efe2c 7001424: implement JSR 292 EG adjustments, November 2010
jrose
parents: 7555
diff changeset
  2825
        }
8821
2836ee97ee27 6839872: remove implementation inheritance from JSR 292 APIs
jrose
parents: 8349
diff changeset
  2826
        return MethodHandleImpl.makeGuardWithCatch(target, exType, handler);
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2827
    }
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2828
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2829
    /**
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2830
     * Produces a method handle which will throw exceptions of the given {@code exType}.
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2831
     * The method handle will accept a single argument of {@code exType},
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2832
     * and immediately throw it as an exception.
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2833
     * The method type will nominally specify a return of {@code returnType}.
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2834
     * The return type may be anything convenient:  It doesn't matter to the
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2835
     * method handle's behavior, since it will never return normally.
18569
0e46c17766b7 8019357: Fix doclint warnings in java.lang.invoke
darcy
parents: 18274
diff changeset
  2836
     * @param returnType the return type of the desired method handle
0e46c17766b7 8019357: Fix doclint warnings in java.lang.invoke
darcy
parents: 18274
diff changeset
  2837
     * @param exType the parameter type of the desired method handle
8346
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2838
     * @return method handle which can throw the given exceptions
3b891698c4ec 7012650: implement JSR 292 EG adjustments through January 2010
jrose
parents: 8345
diff changeset
  2839
     * @throws NullPointerException if either argument is null
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2840
     */
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2841
    public static
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2842
    MethodHandle throwException(Class<?> returnType, Class<? extends Throwable> exType) {
13423
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2843
        if (!Throwable.class.isAssignableFrom(exType))
17843fff200d 7023639: JSR 292 method handle invocation needs a fast path for compiled code
twisti
parents: 13044
diff changeset
  2844
            throw new ClassCastException(exType.getName());
8821
2836ee97ee27 6839872: remove implementation inheritance from JSR 292 APIs
jrose
parents: 8349
diff changeset
  2845
        return MethodHandleImpl.throwException(MethodType.methodType(returnType, exType));
4537
7c3c7f8d5195 6914665: update jdk code for JSR 292 (post 6858164)
jrose
parents: 2764
diff changeset
  2846
    }
2707
5a17df307cbc 6829144: JSR 292 JVM features need a provisional Java API
jrose
parents:
diff changeset
  2847
}