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Java > Open Source Codes > org > jboss > aspects > concurrent > MutexAspect


1 /*
2   * JBoss, Home of Professional Open Source
3   * Copyright 2005, JBoss Inc., and individual contributors as indicated
4   * by the @authors tag. See the copyright.txt in the distribution for a
5   * full listing of individual contributors.
6   *
7   * This is free software; you can redistribute it and/or modify it
8   * under the terms of the GNU Lesser General Public License as
9   * published by the Free Software Foundation; either version 2.1 of
10   * the License, or (at your option) any later version.
11   *
12   * This software is distributed in the hope that it will be useful,
13   * but WITHOUT ANY WARRANTY; without even the implied warranty of
14   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15   * Lesser General Public License for more details.
16   *
17   * You should have received a copy of the GNU Lesser General Public
18   * License along with this software; if not, write to the Free
19   * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20   * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
21   */
22 package org.jboss.aspects.concurrent;
23
24 import org.jboss.aop.joinpoint.Invocation;
25
26 import java.util.concurrent.locks.ReentrantLock JavaDoc;
27
28 /**
29  * comment
30  *
31  * @author <a HREF="mailto:bill@jboss.org">Bill Burke</a>
32  */
33 public class MutexAspect
34 {
35    public static class BlockingMutex
36    {
37       protected MutexLocked props;
38
39       public Object JavaDoc acquire(Invocation invocation) throws Throwable JavaDoc
40       {
41          MutexedObject obj = (MutexedObject) invocation.getTargetObject();
42          ReentrantLock JavaDoc lock = obj.getMutex();
43          try
44          {
45             lock.lockInterruptibly();
46          }
47          catch (InterruptedException JavaDoc e)
48          {
49             throw new LockAcquisitionFailureException("Failed to lock for @Mutexed class", e);
50          }
51
52
53          try
54          {
55             return invocation.invokeNext();
56          }
57          finally
58          {
59             lock.unlock();
60          }
61       }
62    }
63
64    public static class TryLockMutex
65    {
66       protected MutexLocked props;
67
68       public Object JavaDoc acquire(Invocation invocation) throws Throwable JavaDoc
69       {
70          MutexedObject obj = (MutexedObject) invocation.getTargetObject();
71          ReentrantLock JavaDoc lock = obj.getMutex();
72          if (!lock.tryLock())
73          {
74             throw new LockAcquisitionFailureException("Failed to lock for @Mutexed class");
75          }
76
77          try
78          {
79             return invocation.invokeNext();
80          }
81          finally
82          {
83             lock.unlock();
84          }
85       }
86    }
87
88
89    public static class TimeoutMutex
90    {
91       protected MutexLocked props;
92
93       public TimeoutMutex(MutexLocked props)
94       {
95          this.props = props;
96       }
97
98       public Object JavaDoc acquire(Invocation invocation) throws Throwable JavaDoc
99       {
100          MutexedObject obj = (MutexedObject) invocation.getTargetObject();
101          ReentrantLock JavaDoc lock = obj.getMutex();
102          try
103          {
104             if (!lock.tryLock(props.timeout(), props.unit()))
105             {
106                throw new LockAcquisitionFailureException("Failed to acquire permit for @Semaphored class. Timeout reached.");
107             }
108          }
109          catch (InterruptedException JavaDoc e)
110          {
111             throw new LockAcquisitionFailureException("Failed to acquire permit for @Semaphored class", e);
112          }
113
114
115          try
116          {
117             return invocation.invokeNext();
118          }
119          finally
120          {
121             lock.unlock();
122          }
123       }
124    }
125
126
127 }
128
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