src/jdk.dynalink/share/classes/jdk/dynalink/linker/support/Lookup.java
changeset 47216 71c04702a3d5
parent 44555 3a7475e3da26
child 50695 36ca515343e0
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.dynalink/share/classes/jdk/dynalink/linker/support/Lookup.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,402 @@
+/*
+ * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * This file is available under and governed by the GNU General Public
+ * License version 2 only, as published by the Free Software Foundation.
+ * However, the following notice accompanied the original version of this
+ * file, and Oracle licenses the original version of this file under the BSD
+ * license:
+ */
+/*
+   Copyright 2009-2013 Attila Szegedi
+
+   Licensed under both the Apache License, Version 2.0 (the "Apache License")
+   and the BSD License (the "BSD License"), with licensee being free to
+   choose either of the two at their discretion.
+
+   You may not use this file except in compliance with either the Apache
+   License or the BSD License.
+
+   If you choose to use this file in compliance with the Apache License, the
+   following notice applies to you:
+
+       You may obtain a copy of the Apache License at
+
+           http://www.apache.org/licenses/LICENSE-2.0
+
+       Unless required by applicable law or agreed to in writing, software
+       distributed under the License is distributed on an "AS IS" BASIS,
+       WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+       implied. See the License for the specific language governing
+       permissions and limitations under the License.
+
+   If you choose to use this file in compliance with the BSD License, the
+   following notice applies to you:
+
+       Redistribution and use in source and binary forms, with or without
+       modification, are permitted provided that the following conditions are
+       met:
+       * Redistributions of source code must retain the above copyright
+         notice, this list of conditions and the following disclaimer.
+       * Redistributions in binary form must reproduce the above copyright
+         notice, this list of conditions and the following disclaimer in the
+         documentation and/or other materials provided with the distribution.
+       * Neither the name of the copyright holder nor the names of
+         contributors may be used to endorse or promote products derived from
+         this software without specific prior written permission.
+
+       THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+       IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+       TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+       PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDER
+       BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+       CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+       SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+       BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+       WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+       OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+       ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+package jdk.dynalink.linker.support;
+
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.MethodType;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Executable;
+import java.lang.reflect.Field;
+import java.lang.reflect.Method;
+
+/**
+ * A wrapper around {@link java.lang.invoke.MethodHandles.Lookup} that masks
+ * checked exceptions. It is useful in those cases when you're looking up
+ * methods within your own codebase (therefore it is an error if they are not
+ * present).
+ */
+public final class Lookup {
+    private final MethodHandles.Lookup lookup;
+
+    /**
+     * Creates a new instance, bound to an instance of
+     * {@link java.lang.invoke.MethodHandles.Lookup}.
+     *
+     * @param lookup the {@link java.lang.invoke.MethodHandles.Lookup} it delegates to.
+     */
+    public Lookup(final MethodHandles.Lookup lookup) {
+        this.lookup = lookup;
+    }
+
+    /**
+     * A canonical Lookup object that wraps {@link MethodHandles#publicLookup()}.
+     */
+    public static final Lookup PUBLIC = new Lookup(MethodHandles.publicLookup());
+
+    /**
+     * Performs a {@link java.lang.invoke.MethodHandles.Lookup#unreflect(Method)},
+     * converting any encountered {@link IllegalAccessException} into an
+     * {@link IllegalAccessError}.
+     *
+     * @param m the method to unreflect
+     * @return the unreflected method handle.
+     * @throws IllegalAccessError if the method is inaccessible.
+     */
+    public MethodHandle unreflect(final Method m) {
+        return unreflect(lookup, m);
+    }
+
+    /**
+     * Performs a {@link java.lang.invoke.MethodHandles.Lookup#unreflect(Method)},
+     * converting any encountered {@link IllegalAccessException} into an
+     * {@link IllegalAccessError}.
+     *
+     * @param lookup the lookup used to unreflect
+     * @param m the method to unreflect
+     * @return the unreflected method handle.
+     * @throws IllegalAccessError if the method is inaccessible.
+     */
+    public static MethodHandle unreflect(final MethodHandles.Lookup lookup, final Method m) {
+        try {
+            return lookup.unreflect(m);
+        } catch(final IllegalAccessException e) {
+            final IllegalAccessError ee = new IllegalAccessError("Failed to unreflect method " + m);
+            ee.initCause(e);
+            throw ee;
+        }
+    }
+
+    /**
+     * Performs a {@link java.lang.invoke.MethodHandles.Lookup#unreflectGetter(Field)},
+     * converting any encountered {@link IllegalAccessException} into an {@link IllegalAccessError}.
+     *
+     * @param f the field for which a getter is unreflected
+     * @return the unreflected field getter handle.
+     * @throws IllegalAccessError if the getter is inaccessible.
+     */
+    public MethodHandle unreflectGetter(final Field f) {
+        try {
+            return lookup.unreflectGetter(f);
+        } catch(final IllegalAccessException e) {
+            final IllegalAccessError ee = new IllegalAccessError("Failed to unreflect getter for field " + f);
+            ee.initCause(e);
+            throw ee;
+        }
+    }
+
+    /**
+     * Performs a {@link java.lang.invoke.MethodHandles.Lookup#findGetter(Class, String, Class)},
+     * converting any encountered {@link IllegalAccessException} into an
+     * {@link IllegalAccessError} and {@link NoSuchFieldException} into a
+     * {@link NoSuchFieldError}.
+     *
+     * @param refc the class declaring the field
+     * @param name the name of the field
+     * @param type the type of the field
+     * @return the unreflected field getter handle.
+     * @throws IllegalAccessError if the field is inaccessible.
+     * @throws NoSuchFieldError if the field does not exist.
+     */
+    public MethodHandle findGetter(final Class<?>refc, final String name, final Class<?> type) {
+        try {
+            return lookup.findGetter(refc, name, type);
+        } catch(final IllegalAccessException e) {
+            final IllegalAccessError ee = new IllegalAccessError("Failed to access getter for field " + refc.getName() +
+                    "." + name + " of type " + type.getName());
+            ee.initCause(e);
+            throw ee;
+        } catch(final NoSuchFieldException e) {
+            final NoSuchFieldError ee = new NoSuchFieldError("Failed to find getter for field " + refc.getName() +
+                    "." + name + " of type " + type.getName());
+            ee.initCause(e);
+            throw ee;
+        }
+    }
+
+    /**
+     * Performs a {@link java.lang.invoke.MethodHandles.Lookup#unreflectSetter(Field)},
+     * converting any encountered {@link IllegalAccessException} into an
+     * {@link IllegalAccessError}.
+     *
+     * @param f the field for which a setter is unreflected
+     * @return the unreflected field setter handle.
+     * @throws IllegalAccessError if the field is inaccessible.
+     * @throws NoSuchFieldError if the field does not exist.
+     */
+    public MethodHandle unreflectSetter(final Field f) {
+        try {
+            return lookup.unreflectSetter(f);
+        } catch(final IllegalAccessException e) {
+            final IllegalAccessError ee = new IllegalAccessError("Failed to unreflect setter for field " + f);
+            ee.initCause(e);
+            throw ee;
+        }
+    }
+
+    /**
+     * Performs a {@link java.lang.invoke.MethodHandles.Lookup#unreflectConstructor(Constructor)},
+     * converting any encountered {@link IllegalAccessException} into an
+     * {@link IllegalAccessError}.
+     *
+     * @param c the constructor to unreflect
+     * @return the unreflected constructor handle.
+     * @throws IllegalAccessError if the constructor is inaccessible.
+     */
+    public MethodHandle unreflectConstructor(final Constructor<?> c) {
+        return unreflectConstructor(lookup, c);
+    }
+
+    /**
+     * Performs a {@link java.lang.invoke.MethodHandles.Lookup#unreflectConstructor(Constructor)},
+     * converting any encountered {@link IllegalAccessException} into an
+     * {@link IllegalAccessError}.
+     *
+     * @param lookup the lookup used to unreflect
+     * @param c the constructor to unreflect
+     * @return the unreflected constructor handle.
+     * @throws IllegalAccessError if the constructor is inaccessible.
+     */
+    public static MethodHandle unreflectConstructor(final MethodHandles.Lookup lookup, final Constructor<?> c) {
+        try {
+            return lookup.unreflectConstructor(c);
+        } catch(final IllegalAccessException e) {
+            final IllegalAccessError ee = new IllegalAccessError("Failed to unreflect constructor " + c);
+            ee.initCause(e);
+            throw ee;
+        }
+    }
+
+    /**
+     * Performs a {@link java.lang.invoke.MethodHandles.Lookup#findSpecial(Class, String, MethodType, Class)}
+     * on the underlying lookup. Converts any encountered
+     * {@link IllegalAccessException} into an {@link IllegalAccessError} and
+     * {@link NoSuchMethodException} into a {@link NoSuchMethodError}.
+     *
+     * @param declaringClass class declaring the method
+     * @param name the name of the method
+     * @param type the type of the method
+     * @return a method handle for the method
+     * @throws IllegalAccessError if the method is inaccessible.
+     * @throws NoSuchMethodError if the method does not exist.
+     */
+    public MethodHandle findSpecial(final Class<?> declaringClass, final String name, final MethodType type) {
+        try {
+            return lookup.findSpecial(declaringClass, name, type, declaringClass);
+        } catch(final IllegalAccessException e) {
+            final IllegalAccessError ee = new IllegalAccessError("Failed to access special method " + methodDescription(
+                    declaringClass, name, type));
+            ee.initCause(e);
+            throw ee;
+        } catch(final NoSuchMethodException e) {
+            final NoSuchMethodError ee = new NoSuchMethodError("Failed to find special method " + methodDescription(
+                    declaringClass, name, type));
+            ee.initCause(e);
+            throw ee;
+        }
+    }
+
+    private static String methodDescription(final Class<?> declaringClass, final String name, final MethodType type) {
+        return declaringClass.getName() + "#" + name + type;
+    }
+
+    /**
+     * Performs a {@link java.lang.invoke.MethodHandles.Lookup#findStatic(Class, String, MethodType)}
+     * on the underlying lookup. Converts any encountered
+     * {@link IllegalAccessException} into an {@link IllegalAccessError} and
+     * {@link NoSuchMethodException} into a {@link NoSuchMethodError}.
+     *
+     * @param declaringClass class declaring the method
+     * @param name the name of the method
+     * @param type the type of the method
+     * @return a method handle for the method
+     * @throws IllegalAccessError if the method is inaccessible.
+     * @throws NoSuchMethodError if the method does not exist.
+     */
+    public MethodHandle findStatic(final Class<?> declaringClass, final String name, final MethodType type) {
+        try {
+            return lookup.findStatic(declaringClass, name, type);
+        } catch(final IllegalAccessException e) {
+            final IllegalAccessError ee = new IllegalAccessError("Failed to access static method " + methodDescription(
+                    declaringClass, name, type));
+            ee.initCause(e);
+            throw ee;
+        } catch(final NoSuchMethodException e) {
+            final NoSuchMethodError ee = new NoSuchMethodError("Failed to find static method " + methodDescription(
+                    declaringClass, name, type));
+            ee.initCause(e);
+            throw ee;
+        }
+    }
+
+    /**
+     * Performs a {@link java.lang.invoke.MethodHandles.Lookup#findVirtual(Class, String, MethodType)}
+     * on the underlying lookup. Converts any encountered
+     * {@link IllegalAccessException} into an {@link IllegalAccessError} and
+     * {@link NoSuchMethodException} into a {@link NoSuchMethodError}.
+     *
+     * @param declaringClass class declaring the method
+     * @param name the name of the method
+     * @param type the type of the method
+     * @return a method handle for the method
+     * @throws IllegalAccessError if the method is inaccessible.
+     * @throws NoSuchMethodError if the method does not exist.
+     */
+    public MethodHandle findVirtual(final Class<?> declaringClass, final String name, final MethodType type) {
+        try {
+            return lookup.findVirtual(declaringClass, name, type);
+        } catch(final IllegalAccessException e) {
+            final IllegalAccessError ee = new IllegalAccessError("Failed to access virtual method " + methodDescription(
+                    declaringClass, name, type));
+            ee.initCause(e);
+            throw ee;
+        } catch(final NoSuchMethodException e) {
+            final NoSuchMethodError ee = new NoSuchMethodError("Failed to find virtual method " + methodDescription(
+                    declaringClass, name, type));
+            ee.initCause(e);
+            throw ee;
+        }
+    }
+
+    /**
+     * Given a lookup, finds using {@link #findSpecial(Class, String, MethodType)}
+     * a method on that lookup's class. Useful in classes' code for convenient
+     * linking to their own privates.
+     * @param lookup the lookup for the class
+     * @param name the name of the method
+     * @param rtype the return type of the method
+     * @param ptypes the parameter types of the method
+     * @return the method handle for the method
+     */
+    public static MethodHandle findOwnSpecial(final MethodHandles.Lookup lookup, final String name, final Class<?> rtype, final Class<?>... ptypes) {
+        return new Lookup(lookup).findOwnSpecial(name, rtype, ptypes);
+    }
+
+
+    /**
+     * Finds using {@link #findSpecial(Class, String, MethodType)} a method on
+     * that lookup's class. Useful in classes' code for convenient linking to
+     * their own privates. It's also more convenient than {@code findSpecial}
+     * in that you can just list the parameter types, and don't have to specify
+     * lookup class.
+     * @param name the name of the method
+     * @param rtype the return type of the method
+     * @param ptypes the parameter types of the method
+     * @return the method handle for the method
+     */
+    public MethodHandle findOwnSpecial(final String name, final Class<?> rtype, final Class<?>... ptypes) {
+        return findSpecial(lookup.lookupClass(), name, MethodType.methodType(rtype, ptypes));
+    }
+
+    /**
+     * Given a lookup, finds using {@link #findStatic(Class, String, MethodType)}
+     * a method on that lookup's class. Useful in classes' code for convenient
+     * linking to their own privates. It's easier to use than {@code findStatic}
+     * in that you can just list the parameter types, and don't have to specify
+     * lookup class.
+     * @param lookup the lookup for the class
+     * @param name the name of the method
+     * @param rtype the return type of the method
+     * @param ptypes the parameter types of the method
+     * @return the method handle for the method
+     */
+    public static MethodHandle findOwnStatic(final MethodHandles.Lookup lookup, final String name, final Class<?> rtype, final Class<?>... ptypes) {
+        return new Lookup(lookup).findOwnStatic(name, rtype, ptypes);
+    }
+
+    /**
+     * Finds using {@link #findStatic(Class, String, MethodType)} a method on
+     * that lookup's class. Useful in classes' code for convenient linking to
+     * their own privates. It's easier to use than {@code findStatic}
+     * in that you can just list the parameter types, and don't have to specify
+     * lookup class.
+     * @param name the name of the method
+     * @param rtype the return type of the method
+     * @param ptypes the parameter types of the method
+     * @return the method handle for the method
+     */
+    public MethodHandle findOwnStatic(final String name, final Class<?> rtype, final Class<?>... ptypes) {
+        return findStatic(lookup.lookupClass(), name, MethodType.methodType(rtype, ptypes));
+    }
+}