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1
10
11 package org.mule.impl.space;
12
13 import java.util.Iterator  ;
14 import java.util.List ;
15
16 import org.apache.commons.logging.Log;
17 import org.apache.commons.logging.LogFactory;
18 import org.mule.MuleManager;
19 import org.mule.umo.UMOTransactionFactory;
20 import org.mule.umo.space.UMOSpace;
21 import org.mule.umo.space.UMOSpaceEvent;
22 import org.mule.umo.space.UMOSpaceEventListener;
23 import org.mule.umo.space.UMOSpaceException;
24
25 import edu.emory.mathcs.backport.java.util.concurrent.CopyOnWriteArrayList;
26
27
31 public abstract class AbstractSpace implements UMOSpace
32 {
33
34
37 protected transient Log logger = LogFactory.getLog(getClass());
38
39 protected List listeners = new CopyOnWriteArrayList();
40 protected List monitorListeners = new CopyOnWriteArrayList();
41 protected String name;
42 protected boolean enableMonitorEvents;
43 protected UMOTransactionFactory transactionFactory = null;
44
45 protected AbstractSpace(String name)
46 {
47 this(name, true);
48 }
49
50 protected AbstractSpace(String name, boolean enableMonitorEvents)
51 {
52 super();
53 this.name = name;
54 this.enableMonitorEvents = enableMonitorEvents;
55 fireMonitorEvent(SpaceMonitorNotification.SPACE_CREATED, this);
56 }
57
58 public void addListener(UMOSpaceEventListener listener)
59 {
60 listeners.add(listener);
61 fireMonitorEvent(SpaceMonitorNotification.SPACE_LISTENER_ADDED, listener);
62 }
63
64 public void removeListener(UMOSpaceEventListener listener)
65 {
66 listeners.remove(listener);
67 fireMonitorEvent(SpaceMonitorNotification.SPACE_LISTENER_REMOVED, listener);
68 }
69
70 public void addMonitorListener(SpaceMonitorNotificationListener listener)
71 {
72 if (!enableMonitorEvents)
73 {
74 logger.warn("Space monitor notifications for " + name + " space are currently disabled");
75 }
76 monitorListeners.add(listener);
77 }
78
79 public void removeMonitorListener(SpaceMonitorNotificationListener listener)
80 {
81 listeners.remove(listener);
82 }
83
84 public String getName()
85 {
86 return name;
87 }
88
89 public final void put(Object value) throws UMOSpaceException
90 {
91 doPut(value);
92 fireListeners();
93 fireMonitorEvent(SpaceMonitorNotification.SPACE_ITEM_ADDED, value);
94 }
95
96 public void put(Object value, long lease) throws UMOSpaceException
97 {
98 if (logger.isTraceEnabled())
99 {
100 logger.trace("Writing value to space: " + name + ", with lease: " + lease + ", Value is: "
101 + value);
102 }
103 doPut(value, lease);
104 fireListeners();
105 fireMonitorEvent(SpaceMonitorNotification.SPACE_ITEM_ADDED, value);
106 }
107
108 public Object take() throws UMOSpaceException
109 {
110 Object item = doTake();
111
112 if (item == null)
113 {
114 if (logger.isTraceEnabled())
115 {
116 logger.trace("Taking from space: " + name + " returned null");
117 }
118 fireMonitorEvent(SpaceMonitorNotification.SPACE_ITEM_MISS, item);
119 }
120 else
121 {
122 if (logger.isTraceEnabled())
123 {
124 logger.trace("Taking from space: " + name + " returned:" + item);
125 }
126 fireMonitorEvent(SpaceMonitorNotification.SPACE_ITEM_REMOVED, item);
127 }
128 return item;
129 }
130
131 public Object take(long timeout) throws UMOSpaceException
132 {
133 Object item = doTake(timeout);
134 if (item == null)
135 {
136 if (logger.isTraceEnabled())
137 {
138 logger.trace("Taking from space (timeout " + timeout + "): returned null");
139 }
140 fireMonitorEvent(SpaceMonitorNotification.SPACE_ITEM_MISS, item);
141 }
142 else
143 {
144 fireMonitorEvent(SpaceMonitorNotification.SPACE_ITEM_REMOVED, item);
145 if (logger.isTraceEnabled())
146 {
147 logger.trace("Taking from space (timeout " + timeout + "): " + name + " returned:" + item);
148 }
149 }
150 return item;
151 }
152
153 public Object takeNoWait() throws UMOSpaceException
154 {
155 Object item = doTakeNoWait();
156 if (item == null)
157 {
158 fireMonitorEvent(SpaceMonitorNotification.SPACE_ITEM_MISS, item);
159 if (logger.isTraceEnabled())
160 {
161 logger.trace("Taking from space (no wait): " + name + " returned: null");
162 }
163 }
164 else
165 {
166 fireMonitorEvent(SpaceMonitorNotification.SPACE_ITEM_REMOVED, item);
167 if (logger.isTraceEnabled())
168 {
169 logger.trace("Taking from space (no wait): " + name + " returned:" + item);
170 }
171 }
172 return item;
173 }
174
175 protected void fireListeners()
176 {
177 if (listeners.size() > 0)
178 {
179 Object item = null;
180 try
181 {
182 item = takeNoWait();
183 }
184 catch (UMOSpaceException e)
185 {
186 logger.error(e.getMessage(), e);
187 }
188 if (item == null)
189 {
190 logger.warn("Item was taken before listeners could be updated, try using a different type of space");
191 return;
192 }
193 for (Iterator iterator = listeners.iterator(); iterator.hasNext();)
194 {
195 UMOSpaceEventListener spaceEventListener = (UMOSpaceEventListener)iterator.next();
196 spaceEventListener.onEvent(new UMOSpaceEvent(item, this));
197 }
198 }
199 }
200
201 protected void fireMonitorEvent(int action, Object item)
202 {
203 if (enableMonitorEvents)
204 {
205 MuleManager.getInstance().fireNotification(new SpaceMonitorNotification(this, action, item));
206 }
207 }
208
209 public void dispose()
210 {
211 doDispose();
212 fireMonitorEvent(SpaceMonitorNotification.SPACE_DISPOSED, this);
213 }
214
215 public UMOTransactionFactory getTransactionFactory()
216 {
217 return transactionFactory;
218 }
219
220 public void setTransactionFactory(UMOTransactionFactory transactionFactory)
221 {
222 this.transactionFactory = transactionFactory;
223 }
224
225 protected abstract void doPut(Object value) throws UMOSpaceException;
226
227 protected abstract void doPut(Object value, long lease) throws UMOSpaceException;
228
229 protected abstract Object doTake() throws UMOSpaceException;
230
231 protected abstract Object doTake(long timeout) throws UMOSpaceException;
232
233 protected abstract Object doTakeNoWait() throws UMOSpaceException;
234
235 protected abstract void doDispose();
236 }
237 |
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