Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
TurbineSchedulerService |
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| 2.388888888888889;2,389 | ||||
TurbineSchedulerService$MainLoop |
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| 2.388888888888889;2,389 |
1 | package org.apache.turbine.services.schedule; | |
2 | ||
3 | /* | |
4 | * Licensed to the Apache Software Foundation (ASF) under one | |
5 | * or more contributor license agreements. See the NOTICE file | |
6 | * distributed with this work for additional information | |
7 | * regarding copyright ownership. The ASF licenses this file | |
8 | * to you under the Apache License, Version 2.0 (the | |
9 | * "License"); you may not use this file except in compliance | |
10 | * with the License. You may obtain a copy of the License at | |
11 | * | |
12 | * http://www.apache.org/licenses/LICENSE-2.0 | |
13 | * | |
14 | * Unless required by applicable law or agreed to in writing, | |
15 | * software distributed under the License is distributed on an | |
16 | * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY | |
17 | * KIND, either express or implied. See the License for the | |
18 | * specific language governing permissions and limitations | |
19 | * under the License. | |
20 | */ | |
21 | ||
22 | import java.util.Iterator; | |
23 | import java.util.List; | |
24 | ||
25 | import javax.servlet.ServletConfig; | |
26 | ||
27 | import org.apache.commons.logging.Log; | |
28 | import org.apache.commons.logging.LogFactory; | |
29 | import org.apache.torque.TorqueException; | |
30 | import org.apache.torque.util.Criteria; | |
31 | import org.apache.turbine.services.InitializationException; | |
32 | import org.apache.turbine.services.TurbineBaseService; | |
33 | import org.apache.turbine.util.TurbineException; | |
34 | ||
35 | /** | |
36 | * Service for a cron like scheduler. | |
37 | * | |
38 | * @author <a href="mailto:mbryson@mont.mindspring.com">Dave Bryson</a> | |
39 | * @author <a href="mailto:quintonm@bellsouth.net">Quinton McCombs</a> | |
40 | * @version $Id: TurbineSchedulerService.java 534527 2007-05-02 16:10:59Z tv $ | |
41 | */ | |
42 | public class TurbineSchedulerService | |
43 | extends TurbineBaseService | |
44 | implements ScheduleService | |
45 | { | |
46 | /** Logging */ | |
47 | 2 | protected static Log log = LogFactory.getLog(ScheduleService.LOGGER_NAME); |
48 | ||
49 | /** The queue */ | |
50 | 2 | protected JobQueue scheduleQueue = null; |
51 | ||
52 | /** Current status of the scheduler */ | |
53 | 2 | protected boolean enabled = false; |
54 | ||
55 | /** The main loop for starting jobs. */ | |
56 | protected MainLoop mainLoop; | |
57 | ||
58 | /** The thread used to process commands. */ | |
59 | protected Thread thread; | |
60 | ||
61 | /** | |
62 | * Creates a new instance. | |
63 | */ | |
64 | public TurbineSchedulerService() | |
65 | 2 | { |
66 | 2 | mainLoop = null; |
67 | 2 | thread = null; |
68 | 2 | } |
69 | ||
70 | /** | |
71 | * Initializes the SchedulerService. | |
72 | * | |
73 | * @throws InitializationException Something went wrong in the init | |
74 | * stage | |
75 | */ | |
76 | @Override | |
77 | public void init() | |
78 | throws InitializationException | |
79 | { | |
80 | try | |
81 | { | |
82 | 0 | setEnabled(getConfiguration().getBoolean("enabled", true)); |
83 | 0 | scheduleQueue = new JobQueue(); |
84 | 0 | mainLoop = new MainLoop(); |
85 | ||
86 | // Load all from cold storage. | |
87 | 0 | List<JobEntry> jobs = JobEntryPeer.doSelect(new Criteria()); |
88 | ||
89 | 0 | if (jobs != null && jobs.size() > 0) |
90 | { | |
91 | 0 | Iterator<JobEntry> it = jobs.iterator(); |
92 | 0 | while (it.hasNext()) |
93 | { | |
94 | 0 | it.next().calcRunTime(); |
95 | } | |
96 | 0 | scheduleQueue.batchLoad(jobs); |
97 | ||
98 | 0 | restart(); |
99 | } | |
100 | ||
101 | 0 | setInit(true); |
102 | } | |
103 | 0 | catch (Exception e) |
104 | { | |
105 | 0 | String errorMessage = "Could not initialize the scheduler service"; |
106 | 0 | log.error(errorMessage, e); |
107 | 0 | throw new InitializationException(errorMessage, e); |
108 | 0 | } |
109 | 0 | } |
110 | ||
111 | /** | |
112 | * Called the first time the Service is used.<br> | |
113 | * | |
114 | * Load all the jobs from cold storage. Add jobs to the queue | |
115 | * (sorted in ascending order by runtime) and start the scheduler | |
116 | * thread. | |
117 | * | |
118 | * @param config A ServletConfig. | |
119 | * @deprecated use init() instead. | |
120 | */ | |
121 | @Deprecated | |
122 | public void init(ServletConfig config) throws InitializationException | |
123 | { | |
124 | 0 | init(); |
125 | 0 | } |
126 | ||
127 | /** | |
128 | * Shutdowns the service. | |
129 | * | |
130 | * This methods interrupts the housekeeping thread. | |
131 | */ | |
132 | @Override | |
133 | public void shutdown() | |
134 | { | |
135 | 0 | if (getThread() != null) |
136 | { | |
137 | 0 | getThread().interrupt(); |
138 | } | |
139 | 0 | } |
140 | ||
141 | /** | |
142 | * Get a specific Job from Storage. | |
143 | * | |
144 | * @param oid The int id for the job. | |
145 | * @return A JobEntry. | |
146 | * @exception TurbineException job could not be retreived. | |
147 | */ | |
148 | public JobEntry getJob(int oid) | |
149 | throws TurbineException | |
150 | { | |
151 | try | |
152 | { | |
153 | 0 | JobEntry je = JobEntryPeer.retrieveByPK(oid); |
154 | 0 | return scheduleQueue.getJob(je); |
155 | } | |
156 | 0 | catch (TorqueException e) |
157 | { | |
158 | 0 | String errorMessage = "Error retrieving job from persistent storage."; |
159 | 0 | log.error(errorMessage, e); |
160 | 0 | throw new TurbineException(errorMessage, e); |
161 | } | |
162 | } | |
163 | ||
164 | /** | |
165 | * Add a new job to the queue. | |
166 | * | |
167 | * @param je A JobEntry with the job to add. | |
168 | * @throws TurbineException job could not be added | |
169 | */ | |
170 | public void addJob(JobEntry je) | |
171 | throws TurbineException | |
172 | { | |
173 | 0 | updateJob(je); |
174 | 0 | } |
175 | ||
176 | /** | |
177 | * Remove a job from the queue. | |
178 | * | |
179 | * @param je A JobEntry with the job to remove. | |
180 | * @exception TurbineException job could not be removed | |
181 | */ | |
182 | public void removeJob(JobEntry je) | |
183 | throws TurbineException | |
184 | { | |
185 | try | |
186 | { | |
187 | // First remove from DB. | |
188 | 0 | Criteria c = new Criteria().add(JobEntryPeer.JOB_ID, je.getPrimaryKey()); |
189 | 0 | JobEntryPeer.doDelete(c); |
190 | ||
191 | // Remove from the queue. | |
192 | 0 | scheduleQueue.remove(je); |
193 | ||
194 | // restart the scheduler | |
195 | 0 | restart(); |
196 | } | |
197 | 0 | catch (Exception e) |
198 | { | |
199 | 0 | String errorMessage = "Problem removing Scheduled Job: " + je.getTask(); |
200 | 0 | log.error(errorMessage, e); |
201 | 0 | throw new TurbineException(errorMessage, e); |
202 | 0 | } |
203 | 0 | } |
204 | ||
205 | /** | |
206 | * Add or update a job. | |
207 | * | |
208 | * @param je A JobEntry with the job to modify | |
209 | * @throws TurbineException job could not be updated | |
210 | */ | |
211 | public void updateJob(JobEntry je) | |
212 | throws TurbineException | |
213 | { | |
214 | try | |
215 | { | |
216 | 0 | je.calcRunTime(); |
217 | ||
218 | // Update the queue. | |
219 | 0 | if (je.isNew()) |
220 | { | |
221 | 0 | scheduleQueue.add(je); |
222 | } | |
223 | else | |
224 | { | |
225 | 0 | scheduleQueue.modify(je); |
226 | } | |
227 | ||
228 | 0 | je.save(); |
229 | ||
230 | 0 | restart(); |
231 | } | |
232 | 0 | catch (Exception e) |
233 | { | |
234 | 0 | String errorMessage = "Problem updating Scheduled Job: " + je.getTask(); |
235 | 0 | log.error(errorMessage, e); |
236 | 0 | throw new TurbineException(errorMessage, e); |
237 | 0 | } |
238 | 0 | } |
239 | ||
240 | /** | |
241 | * List jobs in the queue. This is used by the scheduler UI. | |
242 | * | |
243 | * @return A List of jobs. | |
244 | */ | |
245 | public List<JobEntry> listJobs() | |
246 | { | |
247 | 6 | return scheduleQueue.list(); |
248 | } | |
249 | ||
250 | /** | |
251 | * Sets the enabled status of the scheduler | |
252 | * | |
253 | * @param enabled | |
254 | * | |
255 | */ | |
256 | protected void setEnabled(boolean enabled) | |
257 | { | |
258 | 4 | this.enabled = enabled; |
259 | 4 | } |
260 | ||
261 | /** | |
262 | * Determines if the scheduler service is currently enabled. | |
263 | * | |
264 | * @return Status of the scheduler service. | |
265 | */ | |
266 | public boolean isEnabled() | |
267 | { | |
268 | 4 | return enabled; |
269 | } | |
270 | ||
271 | /** | |
272 | * Starts or restarts the scheduler if not already running. | |
273 | */ | |
274 | public synchronized void startScheduler() | |
275 | { | |
276 | 2 | setEnabled(true); |
277 | 2 | restart(); |
278 | 2 | } |
279 | ||
280 | /** | |
281 | * Stops the scheduler if it is currently running. | |
282 | */ | |
283 | public synchronized void stopScheduler() | |
284 | { | |
285 | 2 | log.info("Stopping job scheduler"); |
286 | 2 | Thread thread = getThread(); |
287 | 2 | if (thread != null) |
288 | { | |
289 | 2 | thread.interrupt(); |
290 | } | |
291 | 2 | enabled = false; |
292 | 2 | } |
293 | ||
294 | /** | |
295 | * Return the thread being used to process commands, or null if | |
296 | * there is no such thread. You can use this to invoke any | |
297 | * special methods on the thread, for example, to interrupt it. | |
298 | * | |
299 | * @return A Thread. | |
300 | */ | |
301 | public synchronized Thread getThread() | |
302 | { | |
303 | 2 | return thread; |
304 | } | |
305 | ||
306 | /** | |
307 | * Set thread to null to indicate termination. | |
308 | */ | |
309 | protected synchronized void clearThread() | |
310 | { | |
311 | 2 | thread = null; |
312 | 2 | } |
313 | ||
314 | /** | |
315 | * Start (or restart) a thread to process commands, or wake up an | |
316 | * existing thread if one is already running. This method can be | |
317 | * invoked if the background thread crashed due to an | |
318 | * unrecoverable exception in an executed command. | |
319 | */ | |
320 | public synchronized void restart() | |
321 | { | |
322 | 8 | if (enabled) |
323 | { | |
324 | 4 | log.info("Starting job scheduler"); |
325 | 4 | if (thread == null) |
326 | { | |
327 | // Create the the housekeeping thread of the scheduler. It will wait | |
328 | // for the time when the next task needs to be started, and then | |
329 | // launch a worker thread to execute the task. | |
330 | 2 | thread = new Thread(mainLoop, ScheduleService.SERVICE_NAME); |
331 | // Indicate that this is a system thread. JVM will quit only when there | |
332 | // are no more enabled user threads. Settings threads spawned internally | |
333 | // by Turbine as daemons allows commandline applications using Turbine | |
334 | // to terminate in an orderly manner. | |
335 | 2 | thread.setDaemon(true); |
336 | 2 | thread.start(); |
337 | } | |
338 | else | |
339 | { | |
340 | 2 | notify(); |
341 | } | |
342 | } | |
343 | 8 | } |
344 | ||
345 | /** | |
346 | * Return the next Job to execute, or null if thread is | |
347 | * interrupted. | |
348 | * | |
349 | * @return A JobEntry. | |
350 | * @exception TurbineException a generic exception. | |
351 | */ | |
352 | protected synchronized JobEntry nextJob() | |
353 | throws TurbineException | |
354 | { | |
355 | try | |
356 | { | |
357 | 3 | while (!Thread.interrupted()) |
358 | { | |
359 | // Grab the next job off the queue. | |
360 | 3 | JobEntry je = scheduleQueue.getNext(); |
361 | ||
362 | 3 | if (je == null) |
363 | { | |
364 | // Queue must be empty. Wait on it. | |
365 | 0 | wait(); |
366 | } | |
367 | else | |
368 | { | |
369 | 3 | long now = System.currentTimeMillis(); |
370 | 3 | long when = je.getNextRuntime(); |
371 | ||
372 | 3 | if (when > now) |
373 | { | |
374 | // Wait till next runtime. | |
375 | 3 | wait(when - now); |
376 | } | |
377 | else | |
378 | { | |
379 | // Update the next runtime for the job. | |
380 | 0 | scheduleQueue.updateQueue(je); |
381 | // Return the job to run it. | |
382 | 0 | return je; |
383 | } | |
384 | } | |
385 | 1 | } |
386 | } | |
387 | 2 | catch (InterruptedException ex) |
388 | { | |
389 | // ignore | |
390 | 0 | } |
391 | ||
392 | // On interrupt. | |
393 | 2 | return null; |
394 | } | |
395 | ||
396 | /** | |
397 | * Inner class. This is isolated in its own Runnable class just | |
398 | * so that the main class need not implement Runnable, which would | |
399 | * allow others to directly invoke run, which is not supported. | |
400 | */ | |
401 | 2 | protected class MainLoop |
402 | implements Runnable | |
403 | { | |
404 | /** | |
405 | * Method to run the class. | |
406 | */ | |
407 | public void run() | |
408 | { | |
409 | 2 | String taskName = null; |
410 | try | |
411 | { | |
412 | 2 | while (enabled) |
413 | { | |
414 | 2 | JobEntry je = nextJob(); |
415 | 2 | if (je != null) |
416 | { | |
417 | 0 | taskName = je.getTask(); |
418 | ||
419 | // Start the thread to run the job. | |
420 | 0 | Runnable wt = new WorkerThread(je); |
421 | 0 | Thread helper = new Thread(wt); |
422 | 0 | helper.start(); |
423 | } | |
424 | else | |
425 | { | |
426 | break; | |
427 | } | |
428 | 0 | } |
429 | } | |
430 | 0 | catch (Exception e) |
431 | { | |
432 | 0 | log.error("Error running a Scheduled Job: " + taskName, e); |
433 | 0 | enabled = false; |
434 | } | |
435 | finally | |
436 | { | |
437 | 2 | clearThread(); |
438 | 2 | } |
439 | 2 | } |
440 | } | |
441 | } |