01: //
02: // Copyright (C) 2005 United States Government as represented by the
03: // Administrator of the National Aeronautics and Space Administration
04: // (NASA). All Rights Reserved.
05: //
06: // This software is distributed under the NASA Open Source Agreement
07: // (NOSA), version 1.3. The NOSA has been approved by the Open Source
08: // Initiative. See the file NOSA-1.3-JPF at the top of the distribution
09: // directory tree for the complete NOSA document.
10: //
11: // THE SUBJECT SOFTWARE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY OF ANY
12: // KIND, EITHER EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING, BUT NOT
13: // LIMITED TO, ANY WARRANTY THAT THE SUBJECT SOFTWARE WILL CONFORM TO
14: // SPECIFICATIONS, ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR
15: // A PARTICULAR PURPOSE, OR FREEDOM FROM INFRINGEMENT, ANY WARRANTY THAT
16: // THE SUBJECT SOFTWARE WILL BE ERROR FREE, OR ANY WARRANTY THAT
17: // DOCUMENTATION, IF PROVIDED, WILL CONFORM TO THE SUBJECT SOFTWARE.
18: //
19: package gov.nasa.jpf.jvm;
20:
21: import java.util.Hashtable;
22:
23: /**
24: * analogy of DynamicMap to achieve symmetry for static fields (sp that order
25: * of class init does not matter)
26: */
27: public class StaticMap {
28: static Hashtable mapping = new Hashtable();
29: static int counter = 0;
30:
31: public static int getEntry(String cname) {
32: return ((Integer) mapping.get(cname)).intValue();
33: }
34:
35: public static int addEntry(String cname) {
36: Integer index = (Integer) mapping.get(cname);
37:
38: if (index != null) {
39: return index.intValue();
40: }
41: synchronized (StaticMap.class) {
42: index = (Integer) mapping.get(cname);
43:
44: if (index != null) {
45: return index.intValue();
46: }
47:
48: mapping.put(cname, new Integer(counter));
49:
50: return counter++;
51: }
52: }
53:
54: public static boolean hasEntry(String cname) {
55: return mapping.containsKey(cname);
56: }
57:
58: public static synchronized void init() {
59: mapping = new Hashtable();
60: counter = 0;
61: }
62: }
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