| Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
| TurbineSchedulerService |
|
| 2.388888888888889;2,389 | ||||
| TurbineSchedulerService$MainLoop |
|
| 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 | } |