1 /* 2 * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package jdk.nashorn.internal.runtime.linker; 27 28 import static jdk.nashorn.internal.lookup.Lookup.MH; 29 30 import java.lang.invoke.MethodHandle; 31 import java.lang.invoke.MethodType; 32 import jdk.internal.dynalink.CallSiteDescriptor; 33 import jdk.internal.dynalink.linker.GuardedInvocation; 34 import jdk.internal.dynalink.linker.LinkRequest; 35 import jdk.internal.dynalink.support.CallSiteDescriptorFactory; 36 import jdk.internal.dynalink.support.Guards; 37 import jdk.nashorn.internal.lookup.Lookup; 38 import jdk.nashorn.internal.runtime.ScriptObject; 39 40 /** 41 * Implements lookup of methods to link for dynamic operations on JavaScript primitive values (booleans, strings, and 42 * numbers). This class is only public so it can be accessed by classes in the {@code jdk.nashorn.internal.objects} 43 * package. 44 */ 45 public final class PrimitiveLookup { 46 47 private PrimitiveLookup() { 48 } 49 50 /** 51 * Returns a guarded invocation representing the linkage for a dynamic operation on a primitive Java value. 52 * @param request the link request for the dynamic call site. 53 * @param receiverClass the class of the receiver value (e.g., {@link java.lang.Boolean}, {@link java.lang.String} etc.) 54 * @param wrappedReceiver a transient JavaScript native wrapper object created as the object proxy for the primitive 55 * value; see ECMAScript 5.1, section 8.7.1 for discussion of using {@code [[Get]]} on a property reference with a 56 * primitive base value. This instance will be used to delegate actual lookup. 57 * @param wrapFilter A method handle that takes a primitive value of type specified in the {@code receiverClass} and 58 * creates a transient native wrapper of the same type as {@code wrappedReceiver} for subsequent invocations of the 59 * method - it will be combined into the returned invocation as an argument filter on the receiver. 60 * @return a guarded invocation representing the operation at the call site when performed on a JavaScript primitive 61 * type {@code receiverClass}. 62 */ 63 public static GuardedInvocation lookupPrimitive(final LinkRequest request, final Class<?> receiverClass, 64 final ScriptObject wrappedReceiver, final MethodHandle wrapFilter) { 65 return lookupPrimitive(request, Guards.getInstanceOfGuard(receiverClass), wrappedReceiver, wrapFilter); 66 } 67 68 /** 69 * Returns a guarded invocation representing the linkage for a dynamic operation on a primitive Java value. 70 * @param request the link request for the dynamic call site. 71 * @param guard an explicit guard that will be used for the returned guarded invocation. 72 * @param wrappedReceiver a transient JavaScript native wrapper object created as the object proxy for the primitive 73 * value; see ECMAScript 5.1, section 8.7.1 for discussion of using {@code [[Get]]} on a property reference with a 74 * primitive base value. This instance will be used to delegate actual lookup. 75 * @param wrapFilter A method handle that takes a primitive value of type guarded by the {@code guard} and 76 * creates a transient native wrapper of the same type as {@code wrappedReceiver} for subsequent invocations of the 77 * method - it will be combined into the returned invocation as an argument filter on the receiver. 78 * @return a guarded invocation representing the operation at the call site when performed on a JavaScript primitive 79 * type (that is implied by both {@code guard} and {@code wrappedReceiver}). 80 */ 81 public static GuardedInvocation lookupPrimitive(final LinkRequest request, final MethodHandle guard, 82 final ScriptObject wrappedReceiver, final MethodHandle wrapFilter) { 83 final CallSiteDescriptor desc = request.getCallSiteDescriptor(); 84 final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0); 85 if ("setProp".equals(operator) || "setElem".equals(operator)) { 86 MethodType type = desc.getMethodType(); 87 MethodHandle method = MH.asType(Lookup.EMPTY_SETTER, MH.type(void.class, Object.class, type.parameterType(1))); 88 if (type.parameterCount() == 3) { 89 method = MH.dropArguments(method, 2, type.parameterType(2)); 90 } 91 return new GuardedInvocation(method, guard); 92 } 93 94 if(desc.getNameTokenCount() > 2) { 95 final String name = desc.getNameToken(CallSiteDescriptor.NAME_OPERAND); 96 if(wrappedReceiver.findProperty(name, true) == null) { 97 // Give up early, give chance to BeanLinker and NashornBottomLinker to deal with it. 98 return null; 99 } 100 } 101 final GuardedInvocation link = wrappedReceiver.lookup(desc, request); 102 if (link != null) { 103 MethodHandle method = link.getInvocation(); 104 final Class<?> receiverType = method.type().parameterType(0); 105 if (receiverType != Object.class) { 106 final MethodType wrapType = wrapFilter.type(); 107 assert receiverType.isAssignableFrom(wrapType.returnType()); 108 method = MH.filterArguments(method, 0, MH.asType(wrapFilter, wrapType.changeReturnType(receiverType))); 109 } 110 return new GuardedInvocation(method, guard, link.getSwitchPoint()); 111 } 112 return null; 113 } 114 }