1   /**
2    * Copyright (c) 2000-2008 Liferay, Inc. All rights reserved.
3    *
4    * Permission is hereby granted, free of charge, to any person obtaining a copy
5    * of this software and associated documentation files (the "Software"), to deal
6    * in the Software without restriction, including without limitation the rights
7    * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
8    * copies of the Software, and to permit persons to whom the Software is
9    * furnished to do so, subject to the following conditions:
10   *
11   * The above copyright notice and this permission notice shall be included in
12   * all copies or substantial portions of the Software.
13   *
14   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
17   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
20   * SOFTWARE.
21   */
22  
23  package com.liferay.portal.kernel.messaging;
24  
25  import com.liferay.portal.kernel.log.Log;
26  import com.liferay.portal.kernel.log.LogFactoryUtil;
27  import com.liferay.portal.kernel.util.ListUtil;
28  
29  import java.util.HashSet;
30  import java.util.List;
31  import java.util.Set;
32  import java.util.concurrent.ThreadPoolExecutor;
33  
34  /**
35   * <a href="ArrayDispatcherDestination.java.html"><b><i>View Source</i></b></a>
36   *
37   * @author Michael C. Han
38   * @author Brian Wing Shun Chan
39   *
40   */
41  public abstract class ArrayDispatcherDestination extends BaseDestination {
42  
43      public ArrayDispatcherDestination(String name) {
44          super(name);
45      }
46  
47      public ArrayDispatcherDestination(
48          String name, int workersCoreSize, int workersMaxSize) {
49  
50          super(name, workersCoreSize, workersMaxSize);
51      }
52  
53      public synchronized void register(MessageListener listener) {
54          listener = new InvokerMessageListener(listener);
55  
56          Set<MessageListener> listeners = new HashSet<MessageListener>(
57              ListUtil.fromArray(_listeners));
58  
59          listeners.add(listener);
60  
61          _listeners = listeners.toArray(
62              new MessageListener[listeners.size()]);
63      }
64  
65      public void send(Object message) {
66          if (_listeners.length == 0) {
67              if (_log.isDebugEnabled()) {
68                  _log.debug("No listeners for destination " + getName());
69              }
70  
71              return;
72          }
73  
74          ThreadPoolExecutor threadPoolExecutor = getThreadPoolExecutor();
75  
76          if (threadPoolExecutor.isShutdown()) {
77              throw new IllegalStateException(
78                  "Destination " + getName() + " is shutdown and cannot " +
79                      "receive more messages");
80          }
81  
82          dispatch(_listeners, message);
83      }
84  
85      public void send(String message) {
86          if (_listeners.length == 0) {
87              if (_log.isDebugEnabled()) {
88                  _log.debug("No listeners for destination " + getName());
89              }
90  
91              return;
92          }
93  
94          ThreadPoolExecutor threadPoolExecutor = getThreadPoolExecutor();
95  
96          if (threadPoolExecutor.isShutdown()) {
97              throw new IllegalStateException(
98                  "Destination " + getName() + " is shutdown and cannot " +
99                      "receive more messages");
100         }
101 
102         dispatch(_listeners, message);
103     }
104 
105     public synchronized boolean unregister(MessageListener listener) {
106         listener = new InvokerMessageListener(listener);
107 
108         List<MessageListener> listeners = ListUtil.fromArray(_listeners);
109 
110         boolean value = listeners.remove(listener);
111 
112         if (value) {
113             _listeners = listeners.toArray(
114                 new MessageListener[listeners.size()]);
115         }
116 
117         return value;
118     }
119 
120     protected abstract void dispatch(
121         MessageListener[] listeners, Object message);
122 
123     protected abstract void dispatch(
124         MessageListener[] listeners, String message);
125 
126     private static Log _log = LogFactoryUtil.getLog(BaseDestination.class);
127 
128     private MessageListener[] _listeners = new MessageListener[0];
129 
130 }