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Java example source code file (BoundDynamicMethodLinker.java)
The BoundDynamicMethodLinker.java Java example source code/* * 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. */ package jdk.nashorn.internal.runtime.linker; import java.lang.invoke.MethodHandle; import java.lang.invoke.MethodHandles; import java.lang.invoke.MethodType; import jdk.internal.dynalink.CallSiteDescriptor; import jdk.internal.dynalink.beans.BeansLinker; import jdk.internal.dynalink.linker.GuardedInvocation; import jdk.internal.dynalink.linker.LinkRequest; import jdk.internal.dynalink.linker.LinkerServices; import jdk.internal.dynalink.linker.TypeBasedGuardingDynamicLinker; import jdk.internal.dynalink.support.Guards; /** * Links {@code BoundDynamicMethod} objects. Passes through to Dynalink's BeansLinker for linking a dynamic method * (they only respond to "dyn:call"), and modifies the returned invocation to deal with the receiver binding. */ final class BoundDynamicMethodLinker implements TypeBasedGuardingDynamicLinker { @Override public boolean canLinkType(Class<?> type) { return type == BoundDynamicMethod.class; } @Override public GuardedInvocation getGuardedInvocation(LinkRequest linkRequest, LinkerServices linkerServices) throws Exception { final Object objBoundDynamicMethod = linkRequest.getReceiver(); if(!(objBoundDynamicMethod instanceof BoundDynamicMethod)) { return null; } final BoundDynamicMethod boundDynamicMethod = (BoundDynamicMethod)objBoundDynamicMethod; final Object dynamicMethod = boundDynamicMethod.getDynamicMethod(); final Object boundThis = boundDynamicMethod.getBoundThis(); // Replace arguments (boundDynamicMethod, this, ...) => (dynamicMethod, boundThis, ...) when delegating to // BeansLinker final Object[] args = linkRequest.getArguments(); args[0] = dynamicMethod; args[1] = boundThis; // Use R(T0, T1, ...) => R(dynamicMethod.class, boundThis.class, ...) call site type when delegating to // BeansLinker. final CallSiteDescriptor descriptor = linkRequest.getCallSiteDescriptor(); final MethodType type = descriptor.getMethodType(); final Class<?> dynamicMethodClass = dynamicMethod.getClass(); final CallSiteDescriptor newDescriptor = descriptor.changeMethodType( type.changeParameterType(0, dynamicMethodClass).changeParameterType(1, boundThis.getClass())); // Delegate to BeansLinker final GuardedInvocation inv = NashornBeansLinker.getGuardedInvocation(BeansLinker.getLinkerForClass(dynamicMethodClass), linkRequest.replaceArguments(newDescriptor, args), linkerServices); if(inv == null) { return null; } // Bind (dynamicMethod, boundThis) to the handle final MethodHandle boundHandle = MethodHandles.insertArguments(inv.getInvocation(), 0, dynamicMethod, boundThis); final Class<?> p0Type = type.parameterType(0); // Ignore incoming (boundDynamicMethod, this) final MethodHandle droppingHandle = MethodHandles.dropArguments(boundHandle, 0, p0Type, type.parameterType(1)); // Identity guard on boundDynamicMethod object final MethodHandle newGuard = Guards.getIdentityGuard(boundDynamicMethod); return inv.replaceMethods(droppingHandle, newGuard.asType(newGuard.type().changeParameterType(0, p0Type))); } } Other Java examples (source code examples)Here is a short list of links related to this Java BoundDynamicMethodLinker.java source code file: |
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