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Java > Open Source Codes > org > mr > kernel > UniqueIDGenerator


1 /*
2  * Copyright 2002 by
3  * <a HREF="http://www.coridan.com">Coridan</a>
4  * <a HREF="mailto: support@coridan.com ">support@coridan.com</a>
5  *
6  * The contents of this file are subject to the Mozilla Public License Version
7  * 1.1 (the "License"); you may not use this file except in compliance with the
8  * License. You may obtain a copy of the License at
9  * http://www.mozilla.org/MPL/
10  *
11  * Software distributed under the License is distributed on an "AS IS" basis,
12  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
13  * for the specific language governing rights and limitations under the
14  * License.
15  *
16  * The Original Code is "MantaRay" (TM).
17  *
18  * The Initial Developer of the Original Code is Yuval Lubowich.
19  * Portions created by the Initial Developer are Copyright (C) 2006
20  * Coridan Inc. All Rights Reserved.
21  *
22  * Contributor(s): all the names of the contributors are added in the source
23  * code where applicable.
24  *
25  * Alternatively, the contents of this file may be used under the terms of the
26  * LGPL license (the "GNU LESSER GENERAL PUBLIC LICENSE"), in which case the
27  * provisions of LGPL are applicable instead of those above. If you wish to
28  * allow use of your version of this file only under the terms of the LGPL
29  * License and not to allow others to use your version of this file under
30  * the MPL, indicate your decision by deleting the provisions above and
31  * replace them with the notice and other provisions required by the LGPL.
32  * If you do not delete the provisions above, a recipient may use your version
33  * of this file under either the MPL or the GNU LESSER GENERAL PUBLIC LICENSE.
34  
35  *
36  * This library is free software; you can redistribute it and/or modify it
37  * under the terms of the MPL as stated above or under the terms of the GNU
38  * Lesser General Public License as published by the Free Software Foundation;
39  * either version 2.1 of the License, or any later version.
40  *
41  * This library is distributed in the hope that it will be useful, but WITHOUT
42  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
43  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
44  * License for more details.
45  */
46 package org.mr.kernel;
47
48 import java.util.Random JavaDoc;
49
50 import org.mr.core.util.SystemTime;
51
52
53 /**
54  * This class represents a unique id generator for JMS messages.
55  *
56  * @version 1.0
57  * @since Jan 18, 2004
58  * @author Yuval Lubowich
59  *
60  */
61 public class UniqueIDGenerator {
62
63     private static long id = 0;
64     static boolean init = false;
65     
66     /**
67      * Generates a new message GUID.
68      *
69      * @return String the new message ID
70      */
71     public synchronized static long getNextMessageID() {
72          if(!init){
73             id =(random.nextInt() << 32 + (int)(SystemTime.currentTimeMillis() & 0xFFFFFFFF));
74             init = true;
75          }
76          
77          id++;
78          return id;
79     }//getNextMessageID
80
81
82     private static final Random JavaDoc random = new Random JavaDoc();
83 }//UniqueJMSIDGenerator
84
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