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