jdk/src/share/classes/java/lang/invoke/InvokeGeneric.java
changeset 21253 a1e6716bbcbe
parent 21252 74ea5712880f
parent 20543 298a19a1a1f6
child 21254 f6d36ee3f269
--- a/jdk/src/share/classes/java/lang/invoke/InvokeGeneric.java	Fri Oct 11 18:04:45 2013 +0400
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,148 +0,0 @@
-/*
- * Copyright (c) 2009, 2011, 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.
- */
-
-package java.lang.invoke;
-
-import sun.invoke.util.*;
-import static java.lang.invoke.MethodHandles.Lookup.IMPL_LOOKUP;
-
-/**
- * Adapters which manage inexact MethodHandle.invoke calls.
- * The JVM calls one of these when the exact type match fails.
- * @author jrose
- */
-class InvokeGeneric {
-    // erased type for the call, which originates from an inexact invoke site
-    private final MethodType erasedCallerType;
-    // an invoker of type (MT, MH; A...) -> R
-    private final MethodHandle initialInvoker;
-
-    /** Compute and cache information for this adapter, so that it can
-     *  call out to targets of the erasure-family of the given erased type.
-     */
-    /*non-public*/ InvokeGeneric(MethodType erasedCallerType) throws ReflectiveOperationException {
-        assert(erasedCallerType.equals(erasedCallerType.erase()));
-        this.erasedCallerType = erasedCallerType;
-        this.initialInvoker = makeInitialInvoker();
-        assert initialInvoker.type().equals(erasedCallerType
-                                            .insertParameterTypes(0, MethodType.class, MethodHandle.class))
-            : initialInvoker.type();
-    }
-
-    private static MethodHandles.Lookup lookup() {
-        return IMPL_LOOKUP;
-    }
-
-    /** Return the adapter information for this type's erasure. */
-    /*non-public*/ static MethodHandle generalInvokerOf(MethodType erasedCallerType) throws ReflectiveOperationException {
-        InvokeGeneric gen = new InvokeGeneric(erasedCallerType);
-        return gen.initialInvoker;
-    }
-
-    private MethodHandle makeInitialInvoker() throws ReflectiveOperationException {
-        // postDispatch = #(MH'; MT, MH; A...){MH'(MT, MH; A)}
-        MethodHandle postDispatch = makePostDispatchInvoker();
-        MethodHandle invoker;
-        if (returnConversionPossible()) {
-            invoker = MethodHandles.foldArguments(postDispatch,
-                                                  dispatcher("dispatchWithConversion"));
-        } else {
-            invoker = MethodHandles.foldArguments(postDispatch, dispatcher("dispatch"));
-        }
-        return invoker;
-    }
-
-    private static final Class<?>[] EXTRA_ARGS = { MethodType.class, MethodHandle.class };
-    private MethodHandle makePostDispatchInvoker() {
-        // Take (MH'; MT, MH; A...) and run MH'(MT, MH; A...).
-        MethodType invokerType = erasedCallerType.insertParameterTypes(0, EXTRA_ARGS);
-        return invokerType.invokers().exactInvoker();
-    }
-    private MethodHandle dropDispatchArguments(MethodHandle targetInvoker) {
-        assert(targetInvoker.type().parameterType(0) == MethodHandle.class);
-        return MethodHandles.dropArguments(targetInvoker, 1, EXTRA_ARGS);
-    }
-
-    private MethodHandle dispatcher(String dispatchName) throws ReflectiveOperationException {
-        return lookup().bind(this, dispatchName,
-                             MethodType.methodType(MethodHandle.class,
-                                                   MethodType.class, MethodHandle.class));
-    }
-
-    static final boolean USE_AS_TYPE_PATH = true;
-
-    /** Return a method handle to invoke on the callerType, target, and remaining arguments.
-     *  The method handle must finish the call.
-     *  This is the first look at the caller type and target.
-     */
-    private MethodHandle dispatch(MethodType callerType, MethodHandle target) {
-        MethodType targetType = target.type();
-        if (USE_AS_TYPE_PATH || target.isVarargsCollector()) {
-            MethodHandle newTarget = target.asType(callerType);
-            targetType = callerType;
-            Invokers invokers = targetType.invokers();
-            MethodHandle invoker = invokers.erasedInvokerWithDrops;
-            if (invoker == null) {
-                invokers.erasedInvokerWithDrops = invoker =
-                    dropDispatchArguments(invokers.erasedInvoker());
-            }
-            return invoker.bindTo(newTarget);
-        }
-        throw new RuntimeException("NYI");
-    }
-
-    private MethodHandle dispatchWithConversion(MethodType callerType, MethodHandle target) {
-        MethodHandle finisher = dispatch(callerType, target);
-        if (returnConversionNeeded(callerType, target))
-            finisher = addReturnConversion(finisher, callerType.returnType());  //FIXME: slow
-        return finisher;
-    }
-
-    private boolean returnConversionPossible() {
-        Class<?> needType = erasedCallerType.returnType();
-        return !needType.isPrimitive();
-    }
-    private boolean returnConversionNeeded(MethodType callerType, MethodHandle target) {
-        Class<?> needType = callerType.returnType();
-        if (needType == erasedCallerType.returnType())
-            return false;  // no conversions possible, since must be primitive or Object
-        Class<?> haveType = target.type().returnType();
-        if (VerifyType.isNullConversion(haveType, needType) && !needType.isInterface())
-            return false;
-        return true;
-    }
-    private MethodHandle addReturnConversion(MethodHandle finisher, Class<?> type) {
-        // FIXME: This is slow because it creates a closure node on every call that requires a return cast.
-        MethodType finisherType = finisher.type();
-        MethodHandle caster = ValueConversions.identity(type);
-        caster = caster.asType(caster.type().changeParameterType(0, finisherType.returnType()));
-        finisher = MethodHandles.filterReturnValue(finisher, caster);
-        return finisher.asType(finisherType);
-    }
-
-    public String toString() {
-        return "InvokeGeneric"+erasedCallerType;
-    }
-}