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 <em>Attribute</em> and represents a reference 028 * to the source file of this class. At most one SourceFile attribute 029 * should appear per classfile. The intention of this class is that it is 030 * instantiated from the <em>Attribute.readAttribute()</em> method. 031 * 032 * @see Attribute 033 */ 034public final class SourceFile extends Attribute { 035 036 private int sourcefile_index; 037 038 039 /** 040 * Initialize from another object. Note that both objects use the same 041 * references (shallow copy). Use clone() for a physical copy. 042 */ 043 public SourceFile(final SourceFile c) { 044 this(c.getNameIndex(), c.getLength(), c.getSourceFileIndex(), c.getConstantPool()); 045 } 046 047 048 /** 049 * Construct object from input stream. 050 * @param name_index Index in constant pool to CONSTANT_Utf8 051 * @param length Content length in bytes 052 * @param input Input stream 053 * @param constant_pool Array of constants 054 * @throws IOException 055 */ 056 SourceFile(final int name_index, final int length, final DataInput input, final ConstantPool constant_pool) 057 throws IOException { 058 this(name_index, length, input.readUnsignedShort(), constant_pool); 059 } 060 061 062 /** 063 * @param name_index Index in constant pool to CONSTANT_Utf8, which 064 * should represent the string "SourceFile". 065 * @param length Content length in bytes, the value should be 2. 066 * @param constant_pool The constant pool that this attribute is 067 * associated with. 068 * @param sourcefile_index Index in constant pool to CONSTANT_Utf8. This 069 * string will be interpreted as the name of the file from which this 070 * class was compiled. It will not be interpreted as indicating the name 071 * of the directory contqining the file or an absolute path; this 072 * information has to be supplied the consumer of this attribute - in 073 * many cases, the JVM. 074 */ 075 public SourceFile(final int name_index, final int length, final int sourcefile_index, final ConstantPool constant_pool) { 076 super(Const.ATTR_SOURCE_FILE, name_index, length, constant_pool); 077 this.sourcefile_index = sourcefile_index; 078 } 079 080 081 /** 082 * Called by objects that are traversing the nodes of the tree implicitely 083 * defined by the contents of a Java class. I.e., the hierarchy of methods, 084 * fields, attributes, etc. spawns a tree of objects. 085 * 086 * @param v Visitor object 087 */ 088 @Override 089 public void accept( final Visitor v ) { 090 v.visitSourceFile(this); 091 } 092 093 094 /** 095 * Dump source file attribute to file stream in binary format. 096 * 097 * @param file Output file stream 098 * @throws IOException 099 */ 100 @Override 101 public void dump( final DataOutputStream file ) throws IOException { 102 super.dump(file); 103 file.writeShort(sourcefile_index); 104 } 105 106 107 /** 108 * @return Index in constant pool of source file name. 109 */ 110 public int getSourceFileIndex() { 111 return sourcefile_index; 112 } 113 114 115 /** 116 * @param sourcefile_index 117 */ 118 public void setSourceFileIndex( final int sourcefile_index ) { 119 this.sourcefile_index = sourcefile_index; 120 } 121 122 123 /** 124 * @return Source file name. 125 */ 126 public String getSourceFileName() { 127 final ConstantUtf8 c = (ConstantUtf8) super.getConstantPool().getConstant(sourcefile_index, 128 Const.CONSTANT_Utf8); 129 return c.getBytes(); 130 } 131 132 133 /** 134 * @return String representation 135 */ 136 @Override 137 public String toString() { 138 return "SourceFile: " + getSourceFileName(); 139 } 140 141 142 /** 143 * @return deep copy of this attribute 144 */ 145 @Override 146 public Attribute copy( final ConstantPool _constant_pool ) { 147 return (Attribute) clone(); 148 } 149}