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.classfile; 020 021import java.io.DataInput; 022import java.io.DataOutputStream; 023import java.io.IOException; 024 025import org.apache.bcel.Const; 026 027/** 028 * This class is derived from the abstract {@link Constant} and represents a reference to a method handle. 029 * 030 * @see Constant 031 * @since 6.0 032 */ 033public final class ConstantMethodHandle extends Constant { 034 035 private int referenceKind; 036 private int referenceIndex; 037 038 /** 039 * Initialize from another object. 040 * 041 * @param c Source to copy. 042 */ 043 public ConstantMethodHandle(final ConstantMethodHandle c) { 044 this(c.getReferenceKind(), c.getReferenceIndex()); 045 } 046 047 /** 048 * Initialize instance from file data. 049 * 050 * @param file Input stream 051 * @throws IOException if an I/O error occurs. 052 */ 053 ConstantMethodHandle(final DataInput file) throws IOException { 054 this(file.readUnsignedByte(), file.readUnsignedShort()); 055 } 056 057 public ConstantMethodHandle(final int referenceKind, final int referenceIndex) { 058 super(Const.CONSTANT_MethodHandle); 059 this.referenceKind = referenceKind; 060 this.referenceIndex = referenceIndex; 061 } 062 063 /** 064 * Called by objects that are traversing the nodes of the tree implicitly defined by the contents of a Java class. I.e., 065 * the hierarchy of methods, fields, attributes, etc. spawns a tree of objects. 066 * 067 * @param v Visitor object 068 */ 069 @Override 070 public void accept(final Visitor v) { 071 v.visitConstantMethodHandle(this); 072 } 073 074 /** 075 * Dump method kind and index to file stream in binary format. 076 * 077 * @param file Output file stream 078 * @throws IOException if an I/O error occurs. 079 */ 080 @Override 081 public void dump(final DataOutputStream file) throws IOException { 082 file.writeByte(super.getTag()); 083 file.writeByte(referenceKind); 084 file.writeShort(referenceIndex); 085 } 086 087 public int getReferenceIndex() { 088 return referenceIndex; 089 } 090 091 public int getReferenceKind() { 092 return referenceKind; 093 } 094 095 public void setReferenceIndex(final int referenceIndex) { 096 this.referenceIndex = referenceIndex; 097 } 098 099 public void setReferenceKind(final int referenceKind) { 100 this.referenceKind = referenceKind; 101 } 102 103 /** 104 * @return String representation 105 */ 106 @Override 107 public String toString() { 108 return super.toString() + "(referenceKind = " + referenceKind + ", referenceIndex = " + referenceIndex + ")"; 109 } 110}