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Java > Open Source Codes > com > sun > org > apache > bcel > internal > classfile > ConstantNameAndType


1 package com.sun.org.apache.bcel.internal.classfile;
2
3 /* ====================================================================
4  * The Apache Software License, Version 1.1
5  *
6  * Copyright (c) 2001 The Apache Software Foundation. All rights
7  * reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  * 1. Redistributions of source code must retain the above copyright
14  * notice, this list of conditions and the following disclaimer.
15  *
16  * 2. Redistributions in binary form must reproduce the above copyright
17  * notice, this list of conditions and the following disclaimer in
18  * the documentation and/or other materials provided with the
19  * distribution.
20  *
21  * 3. The end-user documentation included with the redistribution,
22  * if any, must include the following acknowledgment:
23  * "This product includes software developed by the
24  * Apache Software Foundation (http://www.apache.org/)."
25  * Alternately, this acknowledgment may appear in the software itself,
26  * if and wherever such third-party acknowledgments normally appear.
27  *
28  * 4. The names "Apache" and "Apache Software Foundation" and
29  * "Apache BCEL" must not be used to endorse or promote products
30  * derived from this software without prior written permission. For
31  * written permission, please contact apache@apache.org.
32  *
33  * 5. Products derived from this software may not be called "Apache",
34  * "Apache BCEL", nor may "Apache" appear in their name, without
35  * prior written permission of the Apache Software Foundation.
36  *
37  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
38  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
39  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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41  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
42  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
43  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
44  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
45  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
46  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
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48  * SUCH DAMAGE.
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50  *
51  * This software consists of voluntary contributions made by many
52  * individuals on behalf of the Apache Software Foundation. For more
53  * information on the Apache Software Foundation, please see
54  * <http://www.apache.org/>.
55  */
56
57 import com.sun.org.apache.bcel.internal.Constants;
58 import java.io.*;
59
60 /**
61  * This class is derived from the abstract
62  * <A HREF="com.sun.org.apache.bcel.internal.classfile.Constant.html">Constant</A> class
63  * and represents a reference to the name and signature
64  * of a field or method.
65  *
66  * @version $Id: ConstantNameAndType.java,v 1.1.1.1 2001/10/29 19:59:59 jvanzyl Exp $
67  * @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
68  * @see Constant
69  */
70 public final class ConstantNameAndType extends Constant {
71   private int name_index; // Name of field/method
72 private int signature_index; // and its signature.
73
74   /**
75    * Initialize from another object.
76    */
77   public ConstantNameAndType(ConstantNameAndType c) {
78     this(c.getNameIndex(), c.getSignatureIndex());
79   }
80  
81   /**
82    * Initialize instance from file data.
83    *
84    * @param file Input stream
85    * @throw IOException
86    */
87   ConstantNameAndType(DataInputStream file) throws IOException
88   {
89     this((int)file.readUnsignedShort(), (int)file.readUnsignedShort());
90   }
91
92   /**
93    * @param name_index Name of field/method
94    * @param signature_index and its signature
95    */
96   public ConstantNameAndType(int name_index,
97                  int signature_index)
98   {
99     super(Constants.CONSTANT_NameAndType);
100     this.name_index = name_index;
101     this.signature_index = signature_index;
102   }
103
104   /**
105    * Called by objects that are traversing the nodes of the tree implicitely
106    * defined by the contents of a Java class. I.e., the hierarchy of methods,
107    * fields, attributes, etc. spawns a tree of objects.
108    *
109    * @param v Visitor object
110    */
111   public void accept(Visitor v) {
112     v.visitConstantNameAndType(this);
113   }
114
115   /**
116    * Dump name and signature index to file stream in binary format.
117    *
118    * @param file Output file stream
119    * @throw IOException
120    */
121   public final void dump(DataOutputStream file) throws IOException
122   {
123     file.writeByte(tag);
124     file.writeShort(name_index);
125     file.writeShort(signature_index);
126   }
127
128   /**
129    * @return Name index in constant pool of field/method name.
130    */
131   public final int getNameIndex() { return name_index; }
132
133   /** @return name
134    */
135   public final String JavaDoc getName(ConstantPool cp) {
136     return cp.constantToString(getNameIndex(), Constants.CONSTANT_Utf8);
137   }
138
139   /**
140    * @return Index in constant pool of field/method signature.
141    */
142   public final int getSignatureIndex() { return signature_index; }
143
144   /** @return signature
145    */
146   public final String JavaDoc getSignature(ConstantPool cp) {
147     return cp.constantToString(getSignatureIndex(), Constants.CONSTANT_Utf8);
148   }
149
150   /**
151    * @param name_index.
152    */
153   public final void setNameIndex(int name_index) {
154     this.name_index = name_index;
155   }
156
157   /**
158    * @param signature_index.
159    */
160   public final void setSignatureIndex(int signature_index) {
161     this.signature_index = signature_index;
162   }
163
164   /**
165    * @return String representation
166    */
167   public final String JavaDoc toString() {
168     return super.toString() + "(name_index = " + name_index +
169       ", signature_index = " + signature_index + ")";
170   }
171 }
172
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