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1 /*
2
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9  Redistribution and use in source and binary forms, with or without modifica-
10  tion, are permitted provided that the following conditions are met:
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22     Alternately, this acknowledgment may appear in the software itself, if
23     and wherever such third-party acknowledgments normally appear.
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25  4. The names "Jakarta", "Avalon", "Excalibur" and "Apache Software Foundation"
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45  This software consists of voluntary contributions made by many individuals
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49 */
50 package org.apache.avalon.excalibur.concurrent;
51
52 /**
53  * Also called counting semaphores, Djikstra semaphores are used to control
54  * access to a set of resources. A Djikstra semaphore has a count associated
55  * with it and each acquire() call reduces the count. A thread that tries to
56  * acquire() a Djikstra semaphore with a zero count blocks until someone else
57  * calls release() thus increasing the count.
58  *
59  * @author <a HREF="mailto:kranga@sapient.com">Karthik Rangaraju</a>
60  * @version CVS $Revision: 1.4 $ $Date: 2003/03/22 12:46:23 $
61  * @since 4.0
62  * @deprecated Replaced by {@link DijkstraSemaphore}.
63  */
64 public class DjikstraSemaphore
65     extends DijkstraSemaphore
66 {
67     /**
68      * Creates a Djikstra semaphore with the specified max count and initial
69      * count set to the max count (all resources released)
70      * @param maxCount is the max semaphores that can be acquired
71      */
72     public DjikstraSemaphore( int maxCount )
73     {
74         super( maxCount, maxCount );
75     }
76
77     /**
78      * Creates a Djikstra semaphore with the specified max count and an initial
79      * count of acquire() operations that are assumed to have already been
80      * performed.
81      * @param maxCount is the max semaphores that can be acquired
82      * @param initialCount is the current count (setting it to zero means all
83      * semaphores have already been acquired). 0 <= initialCount <= maxCount
84      */
85     public DjikstraSemaphore( int maxCount, int initialCount )
86     {
87         super( maxCount, initialCount );
88     }
89 }
90
91
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