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1   /*
2    * Copyright  2000-2004 The Apache Software Foundation
3    *
4    *  Licensed under the Apache License, Version 2.0 (the "License");
5    *  you may not use this file except in compliance with the License.
6    *  You may obtain a copy of the License at
7    *
8    *      http://www.apache.org/licenses/LICENSE-2.0
9    *
10   *  Unless required by applicable law or agreed to in writing, software
11   *  distributed under the License is distributed on an "AS IS" BASIS,
12   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   *  See the License for the specific language governing permissions and
14   *  limitations under the License.
15   *
16   */
17  package org.apache.bcel.classfile;
18  
19  import java.io.DataInputStream;
20  import java.io.DataOutputStream;
21  import java.io.IOException;
22  import org.apache.bcel.Constants;
23  
24  /*** 
25   * This class is derived from the abstract 
26   * <A HREF="org.apache.bcel.classfile.Constant.html">Constant</A> class 
27   * and represents a reference to a Double object.
28   *
29   * @version $Id: ConstantDouble.java 386056 2006-03-15 11:31:56Z tcurdt $
30   * @author  <A HREF="mailto:m.dahm@gmx.de">M. Dahm</A>
31   * @see     Constant
32   */
33  public final class ConstantDouble extends Constant implements ConstantObject {
34  
35      private double bytes;
36  
37  
38      /*** 
39       * @param bytes Data
40       */
41      public ConstantDouble(double bytes) {
42          super(Constants.CONSTANT_Double);
43          this.bytes = bytes;
44      }
45  
46  
47      /***
48       * Initialize from another object.
49       */
50      public ConstantDouble(ConstantDouble c) {
51          this(c.getBytes());
52      }
53  
54  
55      /*** 
56       * Initialize instance from file data.
57       *
58       * @param file Input stream
59       * @throws IOException
60       */
61      ConstantDouble(DataInputStream file) throws IOException {
62          this(file.readDouble());
63      }
64  
65  
66      /***
67       * Called by objects that are traversing the nodes of the tree implicitely
68       * defined by the contents of a Java class. I.e., the hierarchy of methods,
69       * fields, attributes, etc. spawns a tree of objects.
70       *
71       * @param v Visitor object
72       */
73      public void accept( Visitor v ) {
74          v.visitConstantDouble(this);
75      }
76  
77  
78      /***
79       * Dump constant double to file stream in binary format.
80       *
81       * @param file Output file stream
82       * @throws IOException
83       */
84      public final void dump( DataOutputStream file ) throws IOException {
85          file.writeByte(tag);
86          file.writeDouble(bytes);
87      }
88  
89  
90      /***
91       * @return data, i.e., 8 bytes.
92       */
93      public final double getBytes() {
94          return bytes;
95      }
96  
97  
98      /***
99       * @param bytes the raw bytes that represent the double value
100      */
101     public final void setBytes( double bytes ) {
102         this.bytes = bytes;
103     }
104 
105 
106     /***
107      * @return String representation.
108      */
109     public final String toString() {
110         return super.toString() + "(bytes = " + bytes + ")";
111     }
112 
113 
114     /*** @return Double object
115      */
116     public Object getConstantValue( ConstantPool cp ) {
117         return new Double(bytes);
118     }
119 }