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1   /*
2    * reserved comment block
3    * DO NOT REMOVE OR ALTER!
4    */
5   package com.sun.org.apache.bcel.internal.classfile;
6   
7   /* ====================================================================
8    * The Apache Software License, Version 1.1
9    *
10   * Copyright (c) 2001 The Apache Software Foundation.  All rights
11   * reserved.
12   *
13   * Redistribution and use in source and binary forms, with or without
14   * modification, are permitted provided that the following conditions
15   * are met:
16   *
17   * 1. Redistributions of source code must retain the above copyright
18   *    notice, this list of conditions and the following disclaimer.
19   *
20   * 2. Redistributions in binary form must reproduce the above copyright
21   *    notice, this list of conditions and the following disclaimer in
22   *    the documentation and/or other materials provided with the
23   *    distribution.
24   *
25   * 3. The end-user documentation included with the redistribution,
26   *    if any, must include the following acknowledgment:
27   *       "This product includes software developed by the
28   *        Apache Software Foundation (http://www.apache.org/)."
29   *    Alternately, this acknowledgment may appear in the software itself,
30   *    if and wherever such third-party acknowledgments normally appear.
31   *
32   * 4. The names "Apache" and "Apache Software Foundation" and
33   *    "Apache BCEL" must not be used to endorse or promote products
34   *    derived from this software without prior written permission. For
35   *    written permission, please contact apache@apache.org.
36   *
37   * 5. Products derived from this software may not be called "Apache",
38   *    "Apache BCEL", nor may "Apache" appear in their name, without
39   *    prior written permission of the Apache Software Foundation.
40   *
41   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
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43   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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45   * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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47   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
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49   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
50   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
51   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52   * SUCH DAMAGE.
53   * ====================================================================
54   *
55   * This software consists of voluntary contributions made by many
56   * individuals on behalf of the Apache Software Foundation.  For more
57   * information on the Apache Software Foundation, please see
58   * <http://www.apache.org/>.
59   */
60  
61  import  com.sun.org.apache.bcel.internal.Constants;
62  import  java.io.*;
63  
64  /**
65   * This class is derived from <em>Attribute</em> and represents a reference
66   * to the source file of this class.  At most one SourceFile attribute
67   * should appear per classfile.  The intention of this class is that it is
68   * instantiated from the <em>Attribute.readAttribute()</em> method.
69   *
70   * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
71   * @see     Attribute
72   */
73  public final class SourceFile extends Attribute {
74    private int sourcefile_index;
75  
76    /**
77     * Initialize from another object. Note that both objects use the same
78     * references (shallow copy). Use clone() for a physical copy.
79     */
80    public SourceFile(SourceFile c) {
81      this(c.getNameIndex(), c.getLength(), c.getSourceFileIndex(),
82           c.getConstantPool());
83    }
84  
85    /**
86     * Construct object from file stream.
87     * @param name_index Index in constant pool to CONSTANT_Utf8
88     * @param length Content length in bytes
89     * @param file Input stream
90     * @param constant_pool Array of constants
91     * @throws IOException
92     */
93    SourceFile(int name_index, int length, DataInputStream file,
94               ConstantPool constant_pool) throws IOException
95    {
96      this(name_index, length, file.readUnsignedShort(), constant_pool);
97    }
98  
99    /**
100    * @param name_index Index in constant pool to CONSTANT_Utf8, which
101    * should represent the string "SourceFile".
102    * @param length Content length in bytes, the value should be 2.
103    * @param constant_pool The constant pool that this attribute is
104    * associated with.
105    * @param sourcefile_index Index in constant pool to CONSTANT_Utf8.  This
106    * string will be interpreted as the name of the file from which this
107    * class was compiled.  It will not be interpreted as indicating the name
108    * of the directory contqining the file or an absolute path; this
109    * information has to be supplied the consumer of this attribute - in
110    * many cases, the JVM.
111    */
112   public SourceFile(int name_index, int length, int sourcefile_index,
113                     ConstantPool constant_pool)
114   {
115     super(Constants.ATTR_SOURCE_FILE, name_index, length, constant_pool);
116     this.sourcefile_index = sourcefile_index;
117   }
118 
119   /**
120    * Called by objects that are traversing the nodes of the tree implicitely
121    * defined by the contents of a Java class. I.e., the hierarchy of methods,
122    * fields, attributes, etc. spawns a tree of objects.
123    *
124    * @param v Visitor object
125    */
126   public void accept(Visitor v) {
127     v.visitSourceFile(this);
128   }
129 
130   /**
131    * Dump source file attribute to file stream in binary format.
132    *
133    * @param file Output file stream
134    * @throws IOException
135    */
136   public final void dump(DataOutputStream file) throws IOException
137   {
138     super.dump(file);
139     file.writeShort(sourcefile_index);
140   }
141 
142   /**
143    * @return Index in constant pool of source file name.
144    */
145   public final int getSourceFileIndex() { return sourcefile_index; }
146 
147   /**
148    * @param sourcefile_index.
149    */
150   public final void setSourceFileIndex(int sourcefile_index) {
151     this.sourcefile_index = sourcefile_index;
152   }
153 
154   /**
155    * @return Source file name.
156    */
157   public final String getSourceFileName() {
158     ConstantUtf8 c = (ConstantUtf8)constant_pool.getConstant(sourcefile_index,
159                                                              Constants.CONSTANT_Utf8);
160     return c.getBytes();
161   }
162 
163   /**
164    * @return String representation
165    */
166   public final String toString() {
167     return "SourceFile(" + getSourceFileName() + ")";
168   }
169 
170   /**
171    * @return deep copy of this attribute
172    */
173   public Attribute copy(ConstantPool constant_pool) {
174     return (SourceFile)clone();
175   }
176 }