Source code: jacomma/util/Semaphore.java
1 /*
2 * $Source: /home/data/cvsroot/src/jacomma/util/Semaphore.java,v $
3 * $Revision: 1.4 $
4 * $Date: 2000/10/28 20:09:08 $
5 *
6 * This file is part of the jacomma framework
7 * Copyright (c) 2000 Dimitrios Vyzovitis
8 * mailto:dviz@egnatia.ee.auth.gr
9 *
10 *
11 *
12 *
13 *
14 *
15 * This library is free software; you can redistribute it and/or modify
16 * it under the terms of the GNU Library General Public License as published by
17 * the Free Software Foundation; either version 2 of the License, or
18 * (at your option) any later version.
19 *
20 * This library is distributed in the hope that it will be useful,
21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23 * GNU Library General Public License for more details.
24 *
25 * You should have received a copy of the GNU Library General Public License
26 * along with this library; if not, write to the Free Software
27 * Foundation, Inc., 59 Temple Place, Suite 330,
28 * Boston, MA 02111-1307 USA
29 */
30
31 package jacomma.util;
32
33 /**
34 * Simple Semaphore variable (well, not pthread_cond, since this is just synchronization)
35 **/
36 public class Semaphore {
37
38 private int count_;
39
40 public Semaphore() {}
41
42 public synchronized void post() {
43 ++count_;
44 notifyAll();
45 }
46
47 public synchronized int get() { return count_; }
48
49 public synchronized void sem_wait() throws InterruptedException {
50 while( count_ == 0 ) wait();
51 --count_;
52 }
53
54 public synchronized boolean sem_wait( long t ) throws InterruptedException {
55 if ( count_ == 0 ) wait( t );
56 return (count_ > 0) ? (count_-- > 0) : false;
57 }
58
59 }