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1   /*
2    * Copyright (c) 1994, 2003, Oracle and/or its affiliates. All rights reserved.
3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4    *
5    * This code is free software; you can redistribute it and/or modify it
6    * under the terms of the GNU General Public License version 2 only, as
7    * published by the Free Software Foundation.  Oracle designates this
8    * particular file as subject to the "Classpath" exception as provided
9    * by Oracle in the LICENSE file that accompanied this code.
10   *
11   * This code is distributed in the hope that it will be useful, but WITHOUT
12   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14   * version 2 for more details (a copy is included in the LICENSE file that
15   * accompanied this code).
16   *
17   * You should have received a copy of the GNU General Public License version
18   * 2 along with this work; if not, write to the Free Software Foundation,
19   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20   *
21   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22   * or visit www.oracle.com if you need additional information or have any
23   * questions.
24   */
25  
26  package sun.tools.asm;
27  
28  import sun.tools.java.*;
29  import java.io.IOException;
30  import java.io.DataOutputStream;
31  
32  /**
33   * A numeric constant pool item. Can either be integer, float, long or double.
34   *
35   * WARNING: The contents of this source file are not part of any
36   * supported API.  Code that depends on them does so at its own risk:
37   * they are subject to change or removal without notice.
38   */
39  final
40  class NumberConstantData extends ConstantPoolData {
41      Number num;
42  
43      /**
44       * Constructor
45       */
46      NumberConstantData(ConstantPool tab, Number num) {
47          this.num = num;
48      }
49  
50      /**
51       * Write the constant to the output stream
52       */
53      void write(Environment env, DataOutputStream out, ConstantPool tab) throws IOException {
54          if (num instanceof Integer) {
55              out.writeByte(CONSTANT_INTEGER);
56              out.writeInt(num.intValue());
57          } else if (num instanceof Long) {
58              out.writeByte(CONSTANT_LONG);
59              out.writeLong(num.longValue());
60          } else if (num instanceof Float) {
61              out.writeByte(CONSTANT_FLOAT);
62              out.writeFloat(num.floatValue());
63          } else if (num instanceof Double) {
64              out.writeByte(CONSTANT_DOUBLE);
65              out.writeDouble(num.doubleValue());
66          }
67      }
68      /**
69       * Return the order of the constant
70       */
71      int order() {
72          return (width() == 1) ? 0 : 3;
73      }
74  
75      /**
76       * Return the number of entries that it takes up in the constant pool
77       */
78      int width() {
79          return ((num instanceof Double) || (num instanceof Long)) ? 2 : 1;
80      }
81  }