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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
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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.
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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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47   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
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51   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52   * SUCH DAMAGE.
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54   *
55   * This software consists of voluntary contributions made by many
56   * individuals on behalf of the Apache Software Foundation.  For more
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58   * <http://www.apache.org/>.
59   */
60  import java.io.*;
61  import  com.sun.org.apache.bcel.internal.Constants;
62  
63  /**
64   * Abstract super class for Fieldref and Methodref constants.
65   *
66   * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
67   * @see     ConstantFieldref
68   * @see     ConstantMethodref
69   * @see     ConstantInterfaceMethodref
70   */
71  public abstract class ConstantCP extends Constant {
72    /** References to the constants containing the class and the field signature
73     */
74    protected int class_index, name_and_type_index;
75  
76    /**
77     * Initialize from another object.
78     */
79    public ConstantCP(ConstantCP c) {
80      this(c.getTag(), c.getClassIndex(), c.getNameAndTypeIndex());
81    }
82  
83    /**
84     * Initialize instance from file data.
85     *
86     * @param tag  Constant type tag
87     * @param file Input stream
88     * @throws IOException
89     */
90    ConstantCP(byte tag, DataInputStream file) throws IOException
91    {
92      this(tag, file.readUnsignedShort(), file.readUnsignedShort());
93    }
94  
95    /**
96     * @param class_index Reference to the class containing the field
97     * @param name_and_type_index and the field signature
98     */
99    protected ConstantCP(byte tag, int class_index,
100                        int name_and_type_index) {
101     super(tag);
102     this.class_index         = class_index;
103     this.name_and_type_index = name_and_type_index;
104   }
105 
106   /**
107    * Dump constant field reference to file stream in binary format.
108    *
109    * @param file Output file stream
110    * @throws IOException
111    */
112   public final void dump(DataOutputStream file) throws IOException
113   {
114     file.writeByte(tag);
115     file.writeShort(class_index);
116     file.writeShort(name_and_type_index);
117   }
118 
119   /**
120    * @return Reference (index) to class this field or method belongs to.
121    */
122   public final int getClassIndex()       { return class_index; }
123 
124   /**
125    * @return Reference (index) to signature of the field.
126    */
127   public final int getNameAndTypeIndex() { return name_and_type_index; }
128 
129   /**
130    * @param class_index points to Constant_class
131    */
132   public final void setClassIndex(int class_index) {
133     this.class_index = class_index;
134   }
135 
136   /**
137    * @return Class this field belongs to.
138    */
139   public String getClass(ConstantPool cp) {
140     return cp.constantToString(class_index, Constants.CONSTANT_Class);
141   }
142 
143   /**
144    * @param name_and_type_index points to Constant_NameAndType
145    */
146   public final void setNameAndTypeIndex(int name_and_type_index) {
147     this.name_and_type_index = name_and_type_index;
148   }
149 
150   /**
151    * @return String representation.
152    */
153   public final String toString() {
154     return super.toString() + "(class_index = " + class_index +
155       ", name_and_type_index = " + name_and_type_index + ")";
156   }
157 }