Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
WorkerContext |
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| 0.0;0 | ||||
WorkerContext$1 |
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| 0.0;0 |
1 | /* | |
2 | * $Id: WorkerContext.java 19191 2010-08-25 21:05:23Z tcarlson $ | |
3 | * -------------------------------------------------------------------------------------- | |
4 | * Copyright (c) MuleSoft, Inc. All rights reserved. http://www.mulesoft.com | |
5 | * | |
6 | * The software in this package is published under the terms of the CPAL v1.0 | |
7 | * license, a copy of which has been included with this distribution in the | |
8 | * LICENSE.txt file. | |
9 | */ | |
10 | ||
11 | /** | |
12 | * | |
13 | * Copyright 2004 The Apache Software Foundation | |
14 | * | |
15 | * Licensed under the Apache License, Version 2.0 (the "License"); | |
16 | * you may not use this file except in compliance with the License. | |
17 | * You may obtain a copy of the License at | |
18 | * | |
19 | * http://www.apache.org/licenses/LICENSE-2.0 | |
20 | * | |
21 | * Unless required by applicable law or agreed to in writing, software | |
22 | * distributed under the License is distributed on an "AS IS" BASIS, | |
23 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
24 | * See the License for the specific language governing permissions and | |
25 | * limitations under the License. | |
26 | */ | |
27 | ||
28 | package org.mule.work; | |
29 | ||
30 | import org.mule.util.concurrent.Latch; | |
31 | ||
32 | import javax.resource.spi.work.ExecutionContext; | |
33 | import javax.resource.spi.work.Work; | |
34 | import javax.resource.spi.work.WorkAdapter; | |
35 | import javax.resource.spi.work.WorkCompletedException; | |
36 | import javax.resource.spi.work.WorkEvent; | |
37 | import javax.resource.spi.work.WorkException; | |
38 | import javax.resource.spi.work.WorkListener; | |
39 | import javax.resource.spi.work.WorkRejectedException; | |
40 | ||
41 | import org.apache.commons.logging.Log; | |
42 | import org.apache.commons.logging.LogFactory; | |
43 | ||
44 | /** | |
45 | * <code>WorkerContext</code> TODO | |
46 | */ | |
47 | public class WorkerContext implements Work | |
48 | { | |
49 | ||
50 | /** | |
51 | * logger used by this class | |
52 | */ | |
53 | 0 | protected static final Log logger = LogFactory.getLog(WorkerContext.class); |
54 | ||
55 | /** | |
56 | * Null WorkListener used as the default WorkListener. | |
57 | */ | |
58 | 0 | private static final WorkListener NULL_WORK_LISTENER = new WorkAdapter() |
59 | 0 | { |
60 | @Override | |
61 | public void workRejected(WorkEvent event) | |
62 | { | |
63 | 0 | if (event.getException() != null) |
64 | { | |
65 | 0 | if (event.getException() instanceof WorkCompletedException |
66 | && event.getException().getCause() != null) | |
67 | { | |
68 | 0 | logger.error(event.getWork().toString(), event.getException().getCause()); |
69 | } | |
70 | else | |
71 | { | |
72 | 0 | logger.error(event.getWork().toString(), event.getException()); |
73 | } | |
74 | } | |
75 | 0 | } |
76 | }; | |
77 | ||
78 | protected ClassLoader executionClassLoader; | |
79 | ||
80 | /** | |
81 | * Priority of the thread, which will execute this work. | |
82 | */ | |
83 | private int threadPriority; | |
84 | ||
85 | /** | |
86 | * Actual work to be executed. | |
87 | */ | |
88 | private Work worker; | |
89 | ||
90 | /** | |
91 | * System.currentTimeMillis() when the wrapped Work has been accepted. | |
92 | */ | |
93 | private long acceptedTime; | |
94 | ||
95 | /** | |
96 | * Number of times that the execution of this work has been tried. | |
97 | */ | |
98 | private int retryCount; | |
99 | ||
100 | /** | |
101 | * Time duration (in milliseconds) within which the execution of the Work | |
102 | * instance must start. | |
103 | */ | |
104 | private long startTimeOut; | |
105 | ||
106 | /** | |
107 | * Execution context of the actual work to be executed. | |
108 | */ | |
109 | private final ExecutionContext executionContext; | |
110 | ||
111 | /** | |
112 | * Listener to be notified during the life-cycle of the work treatment. | |
113 | */ | |
114 | 0 | private WorkListener workListener = NULL_WORK_LISTENER; |
115 | ||
116 | /** | |
117 | * Work exception, if any. | |
118 | */ | |
119 | private WorkException workException; | |
120 | ||
121 | /** | |
122 | * A latch, which is released when the work is started. | |
123 | */ | |
124 | 0 | private final Latch startLatch = new Latch(); |
125 | ||
126 | /** | |
127 | * A latch, which is released when the work is completed. | |
128 | */ | |
129 | 0 | private final Latch endLatch = new Latch(); |
130 | ||
131 | { | |
132 | 0 | this.executionClassLoader = Thread.currentThread().getContextClassLoader(); |
133 | } | |
134 | ||
135 | /** | |
136 | * Create a WorkWrapper. | |
137 | * | |
138 | * @param work Work to be wrapped. | |
139 | */ | |
140 | public WorkerContext(Work work) | |
141 | 0 | { |
142 | 0 | worker = work; |
143 | 0 | executionContext = null; |
144 | 0 | } |
145 | ||
146 | /** | |
147 | * Create a WorkWrapper with the specified execution context. | |
148 | * | |
149 | * @param aWork Work to be wrapped. | |
150 | * @param aStartTimeout a time duration (in milliseconds) within which the | |
151 | * execution of the Work instance must start. | |
152 | * @param execContext an object containing the execution context with which the | |
153 | * submitted Work instance must be executed. | |
154 | * @param workListener an object which would be notified when the various Work | |
155 | * processing events (work accepted, work rejected, work started, | |
156 | */ | |
157 | public WorkerContext(Work aWork, | |
158 | long aStartTimeout, | |
159 | ExecutionContext execContext, | |
160 | WorkListener workListener) | |
161 | 0 | { |
162 | 0 | worker = aWork; |
163 | 0 | startTimeOut = aStartTimeout; |
164 | 0 | executionContext = execContext; |
165 | 0 | if (null != workListener) |
166 | { | |
167 | 0 | this.workListener = workListener; |
168 | } | |
169 | 0 | } |
170 | ||
171 | public void release() | |
172 | { | |
173 | 0 | worker.release(); |
174 | 0 | } |
175 | ||
176 | /** | |
177 | * Defines the thread priority level of the thread, which will be dispatched to | |
178 | * process this work. This priority level must be the same one for a given | |
179 | * resource adapter. | |
180 | * | |
181 | * @param aPriority Priority of the thread to be used to process the wrapped Work | |
182 | * instance. | |
183 | */ | |
184 | public void setThreadPriority(int aPriority) | |
185 | { | |
186 | 0 | threadPriority = aPriority; |
187 | 0 | } |
188 | ||
189 | /** | |
190 | * Gets the priority level of the thread, which will be dispatched to process | |
191 | * this work. This priority level must be the same one for a given resource | |
192 | * adapter. | |
193 | * | |
194 | * @return The priority level of the thread to be dispatched to process the | |
195 | * wrapped Work instance. | |
196 | */ | |
197 | public int getThreadPriority() | |
198 | { | |
199 | 0 | return threadPriority; |
200 | } | |
201 | ||
202 | /** | |
203 | * Call-back method used by a Work executor in order to notify this instance that | |
204 | * the wrapped Work instance has been accepted. | |
205 | * | |
206 | * @param anObject Object on which the event initially occurred. It should be the | |
207 | * work executor. | |
208 | */ | |
209 | public synchronized void workAccepted(Object anObject) | |
210 | { | |
211 | 0 | acceptedTime = System.currentTimeMillis(); |
212 | 0 | workListener.workAccepted(new WorkEvent(anObject, WorkEvent.WORK_ACCEPTED, worker, null)); |
213 | 0 | } |
214 | ||
215 | /** | |
216 | * System.currentTimeMillis() when the Work has been accepted. This method can be | |
217 | * used to compute the duration of a work. | |
218 | * | |
219 | * @return When the work has been accepted. | |
220 | */ | |
221 | public synchronized long getAcceptedTime() | |
222 | { | |
223 | 0 | return acceptedTime; |
224 | } | |
225 | ||
226 | /** | |
227 | * Gets the time duration (in milliseconds) within which the execution of the | |
228 | * Work instance must start. | |
229 | * | |
230 | * @return Time out duration. | |
231 | */ | |
232 | public long getStartTimeout() | |
233 | { | |
234 | 0 | return startTimeOut; |
235 | } | |
236 | ||
237 | /** | |
238 | * Used by a Work executor in order to know if this work, which should be | |
239 | * accepted but not started has timed out. This method MUST be called prior to | |
240 | * retry the execution of a Work. | |
241 | * | |
242 | * @return true if the Work has timed out and false otherwise. | |
243 | */ | |
244 | public synchronized boolean isTimedOut() | |
245 | { | |
246 | // A value of 0 means that the work never times out. | |
247 | // ??? really? | |
248 | 0 | if (0 == startTimeOut || startTimeOut == MuleWorkManager.INDEFINITE) |
249 | { | |
250 | 0 | return false; |
251 | } | |
252 | 0 | boolean isTimeout = acceptedTime + startTimeOut > 0 |
253 | && System.currentTimeMillis() > acceptedTime + startTimeOut; | |
254 | 0 | if (logger.isDebugEnabled()) |
255 | { | |
256 | 0 | logger.debug(this + " accepted at " + acceptedTime |
257 | + (isTimeout ? " has timed out." : " has not timed out. ") + retryCount | |
258 | + " retries have been performed."); | |
259 | } | |
260 | 0 | if (isTimeout) |
261 | { | |
262 | 0 | workException = new WorkRejectedException(this + " has timed out.", WorkException.START_TIMED_OUT); |
263 | 0 | workListener.workRejected(new WorkEvent(this, WorkEvent.WORK_REJECTED, worker, workException)); |
264 | 0 | return true; |
265 | } | |
266 | 0 | retryCount++; |
267 | 0 | return isTimeout; |
268 | } | |
269 | ||
270 | /** | |
271 | * Gets the WorkException, if any, thrown during the execution. | |
272 | * | |
273 | * @return WorkException, if any. | |
274 | */ | |
275 | public synchronized WorkException getWorkException() | |
276 | { | |
277 | 0 | return workException; |
278 | } | |
279 | ||
280 | public void run() | |
281 | { | |
282 | 0 | if (isTimedOut()) |
283 | { | |
284 | // In case of a time out, one releases the start and end latches | |
285 | // to prevent a dead-lock. | |
286 | 0 | startLatch.countDown(); |
287 | 0 | endLatch.countDown(); |
288 | 0 | return; |
289 | } | |
290 | // Implementation note: the work listener is notified prior to release | |
291 | // the start lock. This behavior is intentional and seems to be the | |
292 | // more conservative. | |
293 | 0 | workListener.workStarted(new WorkEvent(this, WorkEvent.WORK_STARTED, worker, null)); |
294 | 0 | startLatch.countDown(); |
295 | // Implementation note: we assume this is being called without an | |
296 | // interesting TransactionContext, | |
297 | // and ignore/replace whatever is associated with the current thread. | |
298 | try | |
299 | { | |
300 | 0 | if (executionContext == null || executionContext.getXid() == null) |
301 | { | |
302 | // TODO currently unused, see below | |
303 | // ExecutionContext context = new ExecutionContext(); | |
304 | 0 | final ClassLoader originalCl = Thread.currentThread().getContextClassLoader(); |
305 | try | |
306 | { | |
307 | // execute with the application-specific classloader in the context | |
308 | 0 | Thread.currentThread().setContextClassLoader(executionClassLoader); |
309 | 0 | worker.run(); |
310 | } | |
311 | finally | |
312 | { | |
313 | 0 | Thread.currentThread().setContextClassLoader(originalCl); |
314 | ||
315 | // ExecutionContext returningContext = new | |
316 | // ExecutionContext(); | |
317 | // if (context != returningContext) { | |
318 | // throw new WorkCompletedException("Wrong | |
319 | // TransactionContext on return from work done"); | |
320 | // } | |
321 | 0 | } |
322 | // TODO should we commit the txContext to flush any leftover | |
323 | // state??? | |
324 | 0 | } |
325 | else | |
326 | { | |
327 | // try { | |
328 | // long transactionTimeout = | |
329 | // executionContext.getDefaultTransactionTimeout(); | |
330 | // //translate -1 value to 0 to indicate default transaction | |
331 | // timeout. | |
332 | // transactionContextManager.begin(executionContext.getXid(), | |
333 | // transactionTimeout == -1 ? 0 : transactionTimeout); | |
334 | // } catch (XAException e) { | |
335 | // throw new WorkCompletedException("Transaction import failed | |
336 | // for xid " + executionContext.getXid(), | |
337 | // WorkCompletedException.TX_RECREATE_FAILED).initCause(e); | |
338 | // } catch (InvalidTransactionException e) { | |
339 | // throw new WorkCompletedException("Transaction import failed | |
340 | // for xid " + executionContext.getXid(), | |
341 | // WorkCompletedException.TX_RECREATE_FAILED).initCause(e); | |
342 | // } catch (SystemException e) { | |
343 | // throw new WorkCompletedException("Transaction import failed | |
344 | // for xid " + executionContext.getXid(), | |
345 | // WorkCompletedException.TX_RECREATE_FAILED).initCause(e); | |
346 | // } catch (ImportedTransactionActiveException e) { | |
347 | // throw new WorkCompletedException("Transaction already active | |
348 | // for xid " + executionContext.getXid(), | |
349 | // WorkCompletedException.TX_CONCURRENT_WORK_DISALLOWED); | |
350 | // } | |
351 | try | |
352 | { | |
353 | 0 | worker.run(); |
354 | } | |
355 | finally | |
356 | 0 | { |
357 | // transactionContextManager.end(executionContext.getXid()); | |
358 | 0 | } |
359 | ||
360 | } | |
361 | 0 | workListener.workCompleted(new WorkEvent(this, WorkEvent.WORK_COMPLETED, worker, null)); |
362 | } | |
363 | 0 | catch (Throwable e) |
364 | { | |
365 | 0 | workException = (WorkException)(e instanceof WorkCompletedException |
366 | ? e : new WorkCompletedException("Unknown error", | |
367 | WorkCompletedException.UNDEFINED).initCause(e)); | |
368 | 0 | workListener.workCompleted(new WorkEvent(this, WorkEvent.WORK_REJECTED, worker, workException)); |
369 | } | |
370 | finally | |
371 | { | |
372 | 0 | endLatch.countDown(); |
373 | 0 | } |
374 | 0 | } |
375 | ||
376 | /** | |
377 | * Provides a latch, which can be used to wait the start of a work execution. | |
378 | * | |
379 | * @return Latch that a caller can acquire to wait for the start of a work | |
380 | * execution. | |
381 | */ | |
382 | public Latch provideStartLatch() | |
383 | { | |
384 | 0 | return startLatch; |
385 | } | |
386 | ||
387 | /** | |
388 | * Provides a latch, which can be used to wait the end of a work execution. | |
389 | * | |
390 | * @return Latch that a caller can acquire to wait for the end of a work | |
391 | * execution. | |
392 | */ | |
393 | public Latch provideEndLatch() | |
394 | { | |
395 | 0 | return endLatch; |
396 | } | |
397 | ||
398 | @Override | |
399 | public String toString() | |
400 | { | |
401 | 0 | return "Work: " + worker; |
402 | } | |
403 | } |