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.classfile; 019 020import java.io.DataInput; 021import java.io.DataOutputStream; 022import java.io.IOException; 023 024import org.apache.bcel.Const; 025 026/** 027 * This class is derived from the abstract {@link Constant} 028 * 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 reference_kind; 036 private int reference_index; 037 038 039 /** 040 * Initialize from another object. 041 */ 042 public ConstantMethodHandle(final ConstantMethodHandle c) { 043 this(c.getReferenceKind(), c.getReferenceIndex()); 044 } 045 046 047 /** 048 * Initialize instance from file data. 049 * 050 * @param file Input stream 051 * @throws IOException 052 */ 053 ConstantMethodHandle(final DataInput file) throws IOException { 054 this(file.readUnsignedByte(), file.readUnsignedShort()); 055 } 056 057 058 public ConstantMethodHandle(final int reference_kind, final int reference_index) { 059 super(Const.CONSTANT_MethodHandle); 060 this.reference_kind = reference_kind; 061 this.reference_index = reference_index; 062 } 063 064 065 /** 066 * Called by objects that are traversing the nodes of the tree implicitly 067 * defined by the contents of a Java class. I.e., the hierarchy of methods, 068 * fields, attributes, etc. spawns a tree of objects. 069 * 070 * @param v Visitor object 071 */ 072 @Override 073 public void accept( final Visitor v ) { 074 v.visitConstantMethodHandle(this); 075 } 076 077 078 /** 079 * Dump method kind and index to file stream in binary format. 080 * 081 * @param file Output file stream 082 * @throws IOException 083 */ 084 @Override 085 public void dump( final DataOutputStream file ) throws IOException { 086 file.writeByte(super.getTag()); 087 file.writeByte(reference_kind); 088 file.writeShort(reference_index); 089 } 090 091 092 public int getReferenceKind() { 093 return reference_kind; 094 } 095 096 097 public void setReferenceKind(final int reference_kind) { 098 this.reference_kind = reference_kind; 099 } 100 101 102 public int getReferenceIndex() { 103 return reference_index; 104 } 105 106 107 public void setReferenceIndex(final int reference_index) { 108 this.reference_index = reference_index; 109 } 110 111 112 /** 113 * @return String representation 114 */ 115 @Override 116 public String toString() { 117 return super.toString() + "(reference_kind = " + reference_kind + 118 ", reference_index = " + reference_index + ")"; 119 } 120}