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Java > Open Source Codes > org > apache > avalon > excalibur > pool > FixedSizePool


1 /*
2  * Copyright (C) The Apache Software Foundation. All rights reserved.
3  *
4  * This software is published under the terms of the Apache Software License
5  * version 1.1, a copy of which has been included with this distribution in
6  * the LICENSE.txt file.
7  */
8 package org.apache.avalon.excalibur.pool;
9
10 import org.apache.avalon.framework.activity.Disposable;
11 import org.apache.avalon.excalibur.collections.Buffer;
12 import org.apache.avalon.excalibur.collections.FixedSizeBuffer;
13 import org.apache.avalon.excalibur.concurrent.Mutex;
14
15 /**
16  * This is an <code>Pool</code> that caches Poolable objects for reuse.
17  * Please note that this pool offers no resource limiting whatsoever.
18  *
19  * @author <a HREF="mailto:bloritsch@apache.org">Berin Loritsch</a>
20  * @version CVS $Revision: 1.2 $ $Date: 2001/12/26 16:15:23 $
21  * @since 4.1
22  */
23 public final class FixedSizePool
24     implements Pool, Disposable
25 {
26     private boolean m_disposed = false;
27     private final Buffer m_buffer;
28     private final ObjectFactory m_factory;
29     private final Mutex m_mutex = new Mutex();
30
31     public FixedSizePool( ObjectFactory factory, int size )
32         throws Exception JavaDoc
33     {
34         m_buffer = new FixedSizeBuffer( size );
35         m_factory = factory;
36
37         for ( int i = 0; i < size; i++ )
38         {
39             m_buffer.add( m_factory.newInstance() );
40         }
41     }
42
43     public Poolable get()
44     {
45         if ( m_disposed )
46         {
47             throw new IllegalStateException JavaDoc( "Cannot get an object from a disposed pool" );
48         }
49
50         Poolable object = null;
51
52         try
53         {
54             m_mutex.acquire();
55             object = (Poolable) m_buffer.remove();
56         }
57         catch ( InterruptedException JavaDoc ie )
58         {
59             // NOTE: HANDLE THIS
60 }
61         finally
62         {
63             m_mutex.release();
64         }
65
66         return object;
67     }
68
69     public void put( Poolable object )
70     {
71         if ( m_disposed )
72         {
73             try
74             {
75                 m_factory.decommission( object );
76             }
77             catch ( Exception JavaDoc e )
78             {
79                 // We should never get here, but ignore the exception if it happens
80 }
81         }
82         else
83         {
84             try
85             {
86                 m_mutex.acquire();
87                 m_buffer.add( object );
88             }
89             catch ( InterruptedException JavaDoc e )
90             {
91               // NOTE: HANDLE THIS
92 }
93             finally
94             {
95                 m_mutex.release();
96             }
97         }
98     }
99
100     public void dispose()
101     {
102         m_disposed = true;
103
104         try
105         {
106             m_mutex.acquire();
107
108             while ( ! m_buffer.isEmpty() )
109             {
110                 try
111                 {
112                     m_factory.decommission( m_buffer.remove() );
113                 }
114                 catch ( Exception JavaDoc e )
115                 {
116                     // We should never get here, but ignore the exception if it happens
117 }
118             }
119         }
120         catch ( InterruptedException JavaDoc ie )
121         {
122             // NOTE: HANDLE THIS
123 }
124         finally
125         {
126             m_mutex.release();
127         }
128     }
129 }
130
131
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