001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * https://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 */ 019package org.apache.bcel.generic; 020 021import java.io.DataOutputStream; 022import java.io.IOException; 023 024import org.apache.bcel.Const; 025import org.apache.bcel.ExceptionConst; 026import org.apache.bcel.classfile.ConstantInvokeDynamic; 027import org.apache.bcel.classfile.ConstantNameAndType; 028import org.apache.bcel.classfile.ConstantPool; 029import org.apache.bcel.util.ByteSequence; 030 031/** 032 * Class for INVOKEDYNAMIC. Not an instance of InvokeInstruction, since that class expects to be able to get the class 033 * of the method. Ignores the bootstrap mechanism entirely. 034 * 035 * @see <a href="https://docs.oracle.com/javase/specs/jvms/se8/html/jvms-6.html#jvms-6.5.invokedynamic"> The 036 * invokedynamic instruction in The Java Virtual Machine Specification</a> 037 * @since 6.0 038 */ 039public class INVOKEDYNAMIC extends InvokeInstruction { 040 041 /** 042 * Empty constructor needed for Instruction.readInstruction. Not to be used otherwise. 043 */ 044 INVOKEDYNAMIC() { 045 } 046 047 public INVOKEDYNAMIC(final int index) { 048 super(Const.INVOKEDYNAMIC, index); 049 } 050 051 /** 052 * Call corresponding visitor method(s). The order is: Call visitor methods of implemented interfaces first, then call 053 * methods according to the class hierarchy in descending order, i.e., the most specific visitXXX() call comes last. 054 * 055 * @param v Visitor object 056 */ 057 @Override 058 public void accept(final Visitor v) { 059 v.visitExceptionThrower(this); 060 v.visitTypedInstruction(this); 061 v.visitStackConsumer(this); 062 v.visitStackProducer(this); 063 v.visitLoadClass(this); 064 v.visitCPInstruction(this); 065 v.visitFieldOrMethod(this); 066 v.visitInvokeInstruction(this); 067 v.visitINVOKEDYNAMIC(this); 068 } 069 070 /** 071 * Dump instruction as byte code to stream out. 072 * 073 * @param out Output stream 074 */ 075 @Override 076 public void dump(final DataOutputStream out) throws IOException { 077 out.writeByte(super.getOpcode()); 078 out.writeShort(super.getIndex()); 079 out.writeByte(0); 080 out.writeByte(0); 081 } 082 083 /** 084 * Override the parent method because our class name is held elsewhere. 085 * 086 * Note: Contrary to this method's name it does not return the class name of the invoke target; rather it returns the 087 * name of the method that will be used to invoke the Lambda method generated by this invoke dynamic instruction. 088 */ 089 @Override 090 public String getClassName(final ConstantPoolGen cpg) { 091 final ConstantPool cp = cpg.getConstantPool(); 092 final ConstantInvokeDynamic cid = cp.getConstant(super.getIndex(), Const.CONSTANT_InvokeDynamic, ConstantInvokeDynamic.class); 093 return cp.getConstant(cid.getNameAndTypeIndex(), ConstantNameAndType.class).getName(cp); 094 } 095 096 @Override 097 public Class<?>[] getExceptions() { 098 return ExceptionConst.createExceptions(ExceptionConst.EXCS.EXCS_INTERFACE_METHOD_RESOLUTION, ExceptionConst.UNSATISFIED_LINK_ERROR, 099 ExceptionConst.ABSTRACT_METHOD_ERROR, ExceptionConst.ILLEGAL_ACCESS_ERROR, ExceptionConst.INCOMPATIBLE_CLASS_CHANGE_ERROR); 100 } 101 102 /** 103 * Since InvokeDynamic doesn't refer to a reference type, just return {@link Object}, as that is the only type we can 104 * say for sure the reference will be. 105 * 106 * @param cpg the ConstantPoolGen used to create the instruction 107 * @return an ObjectType for {@link Object} 108 * @since 6.1 109 */ 110 @Override 111 public ReferenceType getReferenceType(final ConstantPoolGen cpg) { 112 return new ObjectType(Object.class.getName()); 113 } 114 115 /** 116 * Reads needed data (i.e., index) from file. 117 */ 118 @Override 119 protected void initFromFile(final ByteSequence bytes, final boolean wide) throws IOException { 120 super.initFromFile(bytes, wide); 121 super.setLength(5); 122 bytes.readByte(); // Skip 0 byte 123 bytes.readByte(); // Skip 0 byte 124 } 125 126}