1   /**
2    * Copyright (c) 2000-2009 Liferay, Inc. All rights reserved.
3    *
4    *
5    *
6    *
7    * The contents of this file are subject to the terms of the Liferay Enterprise
8    * Subscription License ("License"). You may not use this file except in
9    * compliance with the License. You can obtain a copy of the License by
10   * contacting Liferay, Inc. See the License for the specific language governing
11   * permissions and limitations under the License, including but not limited to
12   * distribution rights 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.ConcurrentHashSet;
28  
29  import java.util.Collection;
30  import java.util.HashMap;
31  import java.util.Map;
32  import java.util.Set;
33  
34  /**
35   * <a href="DefaultMessageBus.java.html"><b><i>View Source</i></b></a>
36   *
37   * @author Michael C. Han
38   */
39  public class DefaultMessageBus implements MessageBus {
40  
41      public synchronized void addDestination(Destination destination) {
42          _destinations.put(destination.getName(), destination);
43  
44          fireDestinationAddedEvent(destination);
45      }
46  
47      public void addDestinationEventListener(
48          DestinationEventListener destinationEventListener) {
49  
50          _destinationEventListeners.add(destinationEventListener);
51      }
52  
53      public void addDestinationEventListener(
54          String destinationName,
55          DestinationEventListener destinationEventListener) {
56  
57          Destination destination = _destinations.get(destinationName);
58  
59          if (destination != null) {
60              destination.addDestinationEventListener(destinationEventListener);
61          }
62      }
63  
64      public void destroy() {
65          shutdown(true);
66      }
67  
68      public Destination getDestination(String destinationName) {
69          return _destinations.get(destinationName);
70      }
71  
72      public int getDestinationCount() {
73          return _destinations.size();
74      }
75  
76      public Collection<String> getDestinationNames() {
77          return _destinations.keySet();
78      }
79  
80      public Collection<Destination> getDestinations() {
81          return _destinations.values();
82      }
83  
84      public boolean hasDestination(String destinationName) {
85          return _destinations.containsKey(destinationName);
86      }
87  
88      public boolean hasMessageListener(String destinationName) {
89          Destination destination = _destinations.get(destinationName);
90  
91          if ((destination != null) && destination.isRegistered()) {
92              return true;
93          }
94          else {
95              return false;
96          }
97      }
98  
99      public synchronized boolean registerMessageListener(
100         String destinationName, MessageListener messageListener) {
101 
102         Destination destination = _destinations.get(destinationName);
103 
104         if (destination == null) {
105             throw new IllegalStateException(
106                 "Destination " + destinationName + " is not configured");
107         }
108 
109         boolean registered = destination.register(messageListener);
110 
111         if (registered) {
112             fireMessageListenerRegisteredEvent(destination, messageListener);
113         }
114 
115         return registered;
116     }
117 
118     public synchronized Destination removeDestination(String destinationName) {
119         Destination destinationModel = _destinations.remove(destinationName);
120 
121         destinationModel.removeDestinationEventListeners();
122         destinationModel.unregisterMessageListeners();
123 
124         fireDestinationRemovedEvent(destinationModel);
125 
126         return destinationModel;
127     }
128 
129     public void removeDestinationEventListener(
130         DestinationEventListener destinationEventListener) {
131 
132         _destinationEventListeners.remove(destinationEventListener);
133     }
134 
135     public void removeDestinationEventListener(
136         String destinationName,
137         DestinationEventListener destinationEventListener) {
138 
139         Destination destination = _destinations.get(destinationName);
140 
141         if (destination != null) {
142             destination.removeDestinationEventListener(
143                 destinationEventListener);
144         }
145     }
146 
147     public void replace(Destination destination) {
148         Destination oldDestination = _destinations.get(destination.getName());
149 
150         oldDestination.copyDestinationEventListeners(destination);
151         oldDestination.copyMessageListeners(destination);
152 
153         removeDestination(oldDestination.getName());
154 
155         addDestination(destination);
156     }
157 
158     public void sendMessage(String destinationName, Message message) {
159         Destination destination = _destinations.get(destinationName);
160 
161         if (destination == null) {
162             if (_log.isWarnEnabled()) {
163                 _log.warn(
164                     "Destination " + destinationName + " is not configured");
165             }
166 
167             return;
168         }
169 
170         message.setDestinationName(destinationName);
171 
172         destination.send(message);
173     }
174 
175     public void shutdown() {
176         shutdown(false);
177     }
178 
179     public synchronized void shutdown(boolean force) {
180         for (Destination destination : _destinations.values()) {
181             destination.close(force);
182         }
183     }
184 
185     public synchronized boolean unregisterMessageListener(
186         String destinationName, MessageListener messageListener) {
187 
188         Destination destination = _destinations.get(destinationName);
189 
190         if (destination == null) {
191             return false;
192         }
193 
194         boolean unregistered = destination.unregister(messageListener);
195 
196         if (unregistered) {
197             fireMessageListenerUnregisteredEvent(destination, messageListener);
198         }
199 
200         return unregistered;
201     }
202 
203     protected void fireDestinationAddedEvent(Destination destination) {
204         for (DestinationEventListener listener : _destinationEventListeners) {
205             listener.destinationAdded(destination);
206         }
207     }
208 
209     protected void fireDestinationRemovedEvent(Destination destination) {
210         for (DestinationEventListener listener : _destinationEventListeners) {
211             listener.destinationRemoved(destination);
212         }
213     }
214 
215     protected void fireMessageListenerRegisteredEvent(
216         Destination destination, MessageListener messageListener) {
217 
218         for (DestinationEventListener destinationEventListener :
219                 _destinationEventListeners) {
220 
221             destinationEventListener.messageListenerRegistered(
222                 destination.getName(), messageListener);
223         }
224     }
225 
226     protected void fireMessageListenerUnregisteredEvent(
227         Destination destination, MessageListener messageListener) {
228 
229         for (DestinationEventListener destinationEventListener :
230                 _destinationEventListeners) {
231 
232             destinationEventListener.messageListenerUnregistered(
233                 destination.getName(), messageListener);
234         }
235     }
236 
237     private static Log _log = LogFactoryUtil.getLog(DefaultMessageBus.class);
238 
239     private Set<DestinationEventListener> _destinationEventListeners =
240         new ConcurrentHashSet<DestinationEventListener>();
241     private Map<String, Destination> _destinations =
242         new HashMap<String, Destination>();
243 
244 }