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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.
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41   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
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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 the abstract
66   * <A HREF="com.sun.org.apache.bcel.internal.classfile.Constant.html">Constant</A> class
67   * and represents a reference to the name and signature
68   * of a field or method.
69   *
70   * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
71   * @see     Constant
72   */
73  public final class ConstantNameAndType extends Constant {
74    private int name_index;      // Name of field/method
75    private int signature_index; // and its signature.
76  
77    /**
78     * Initialize from another object.
79     */
80    public ConstantNameAndType(ConstantNameAndType c) {
81      this(c.getNameIndex(), c.getSignatureIndex());
82    }
83  
84    /**
85     * Initialize instance from file data.
86     *
87     * @param file Input stream
88     * @throws IOException
89     */
90    ConstantNameAndType(DataInputStream file) throws IOException
91    {
92      this((int)file.readUnsignedShort(), (int)file.readUnsignedShort());
93    }
94  
95    /**
96     * @param name_index Name of field/method
97     * @param signature_index and its signature
98     */
99    public ConstantNameAndType(int name_index,
100                              int signature_index)
101   {
102     super(Constants.CONSTANT_NameAndType);
103     this.name_index      = name_index;
104     this.signature_index = signature_index;
105   }
106 
107   /**
108    * Called by objects that are traversing the nodes of the tree implicitely
109    * defined by the contents of a Java class. I.e., the hierarchy of methods,
110    * fields, attributes, etc. spawns a tree of objects.
111    *
112    * @param v Visitor object
113    */
114   public void accept(Visitor v) {
115     v.visitConstantNameAndType(this);
116   }
117 
118   /**
119    * Dump name and signature index to file stream in binary format.
120    *
121    * @param file Output file stream
122    * @throws IOException
123    */
124   public final void dump(DataOutputStream file) throws IOException
125   {
126     file.writeByte(tag);
127     file.writeShort(name_index);
128     file.writeShort(signature_index);
129   }
130 
131   /**
132    * @return Name index in constant pool of field/method name.
133    */
134   public final int getNameIndex()      { return name_index; }
135 
136   /** @return name
137    */
138   public final String getName(ConstantPool cp) {
139     return cp.constantToString(getNameIndex(), Constants.CONSTANT_Utf8);
140   }
141 
142   /**
143    * @return Index in constant pool of field/method signature.
144    */
145   public final int getSignatureIndex() { return signature_index; }
146 
147   /** @return signature
148    */
149   public final String getSignature(ConstantPool cp) {
150     return cp.constantToString(getSignatureIndex(), Constants.CONSTANT_Utf8);
151   }
152 
153   /**
154    * @param name_index.
155    */
156   public final void setNameIndex(int name_index) {
157     this.name_index = name_index;
158   }
159 
160   /**
161    * @param signature_index.
162    */
163   public final void setSignatureIndex(int signature_index) {
164     this.signature_index = signature_index;
165   }
166 
167   /**
168    * @return String representation
169    */
170   public final String toString() {
171     return super.toString() + "(name_index = " + name_index +
172       ", signature_index = " + signature_index + ")";
173   }
174 }