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 * @version $Id: SourceFile.java 1749603 2016-06-21 20:50:19Z ggregory $
033 * @see     Attribute
034 */
035public final class SourceFile extends Attribute {
036
037    private int sourcefile_index;
038
039
040    /**
041     * Initialize from another object. Note that both objects use the same
042     * references (shallow copy). Use clone() for a physical copy.
043     */
044    public SourceFile(final SourceFile c) {
045        this(c.getNameIndex(), c.getLength(), c.getSourceFileIndex(), c.getConstantPool());
046    }
047
048
049    /**
050     * Construct object from input stream.
051     * @param name_index Index in constant pool to CONSTANT_Utf8
052     * @param length Content length in bytes
053     * @param input Input stream
054     * @param constant_pool Array of constants
055     * @throws IOException
056     */
057    SourceFile(final int name_index, final int length, final DataInput input, final ConstantPool constant_pool)
058            throws IOException {
059        this(name_index, length, input.readUnsignedShort(), constant_pool);
060    }
061
062
063    /**
064     * @param name_index Index in constant pool to CONSTANT_Utf8, which
065     * should represent the string "SourceFile".
066     * @param length Content length in bytes, the value should be 2.
067     * @param constant_pool The constant pool that this attribute is
068     * associated with.
069     * @param sourcefile_index Index in constant pool to CONSTANT_Utf8.  This
070     * string will be interpreted as the name of the file from which this
071     * class was compiled.  It will not be interpreted as indicating the name
072     * of the directory contqining the file or an absolute path; this
073     * information has to be supplied the consumer of this attribute - in
074     * many cases, the JVM.
075     */
076    public SourceFile(final int name_index, final int length, final int sourcefile_index, final ConstantPool constant_pool) {
077        super(Const.ATTR_SOURCE_FILE, name_index, length, constant_pool);
078        this.sourcefile_index = sourcefile_index;
079    }
080
081
082    /**
083     * Called by objects that are traversing the nodes of the tree implicitely
084     * defined by the contents of a Java class. I.e., the hierarchy of methods,
085     * fields, attributes, etc. spawns a tree of objects.
086     *
087     * @param v Visitor object
088     */
089    @Override
090    public void accept( final Visitor v ) {
091        v.visitSourceFile(this);
092    }
093
094
095    /**
096     * Dump source file attribute to file stream in binary format.
097     *
098     * @param file Output file stream
099     * @throws IOException
100     */
101    @Override
102    public final void dump( final DataOutputStream file ) throws IOException {
103        super.dump(file);
104        file.writeShort(sourcefile_index);
105    }
106
107
108    /**
109     * @return Index in constant pool of source file name.
110     */
111    public final int getSourceFileIndex() {
112        return sourcefile_index;
113    }
114
115
116    /**
117     * @param sourcefile_index
118     */
119    public final void setSourceFileIndex( final int sourcefile_index ) {
120        this.sourcefile_index = sourcefile_index;
121    }
122
123
124    /**
125     * @return Source file name.
126     */
127    public final String getSourceFileName() {
128        final ConstantUtf8 c = (ConstantUtf8) super.getConstantPool().getConstant(sourcefile_index,
129                Const.CONSTANT_Utf8);
130        return c.getBytes();
131    }
132
133
134    /**
135     * @return String representation
136     */
137    @Override
138    public final String toString() {
139        return "SourceFile: " + getSourceFileName();
140    }
141
142
143    /**
144     * @return deep copy of this attribute
145     */
146    @Override
147    public Attribute copy( final ConstantPool _constant_pool ) {
148        return (Attribute) clone();
149    }
150}