quartz原理分析2----job和trigger的存储

2018年07月16日 16:44:56 李民11 阅读数：254

    对于数据库模式的调度任务，job和trigger需要被存储到数据库中。当服务器再次启动的时候调度任务可以继续执行。

    下面分析任务的存储代码。

1. public static void main(String[] args) throws SchedulerException {

2.  

3. SchedulerFactory sf = new StdSchedulerFactory();

4.  

5. Scheduler scheduler = sf.getScheduler();

6.  

7. scheduler.pauseJob(JobKey.jobKey("ramJob", "ramGroup"));

8. scheduler.pauseTrigger(TriggerKey.triggerKey("ramTrigger", "ramTriggerGroup"));

9. scheduler.unscheduleJob(TriggerKey.triggerKey("ramTrigger", "ramTriggerGroup"));

10. scheduler.deleteJob(JobKey.jobKey("ramJob", "ramGroup"));

11.  

12. //job

13. JobDetail jb = JobBuilder.newJob(RamJob.class).withDescription("description:ram job")

14. .withIdentity("ramJob", "ramGroup").build();

15.  

16. //trigger

17. Trigger trigger = TriggerBuilder.newTrigger().withDescription("ram trigger")

18. .withIdentity("ramTrigger", "ramTriggerGroup").startAt(new Date(System.currentTimeMillis() + 3 * 1000))

19. .withSchedule(CronScheduleBuilder.cronSchedule("0/2 * * * * ?")).build();

20.  

21. //包含存储操作

22. scheduler.scheduleJob(jb, trigger);

23.  

24. scheduler.start();

25. }

    Schedule.scheduleJob方法执行存储操作。

1. public Date scheduleJob(JobDetail jobDetail, Trigger trigger)

2. throws SchedulerException {

3. return sched.scheduleJob(jobDetail, trigger);

4. }

    sched是 QuartzScheduler实例，包含存储job和trigger的方法。 

1. public Date scheduleJob(JobDetail jobDetail,

2. Trigger trigger) throws SchedulerException {

3. validateState();

4.  

5. if (jobDetail == null) {

6. throw new SchedulerException("JobDetail cannot be null");

7. }

8.  

9. if (trigger == null) {

10. throw new SchedulerException("Trigger cannot be null");

11. }

12.  

13. if (jobDetail.getKey() == null) {

14. throw new SchedulerException("Job's key cannot be null");

15. }

16.  

17. if (jobDetail.getJobClass() == null) {

18. throw new SchedulerException("Job's class cannot be null");

19. }

20.  

21. OperableTrigger trig = (OperableTrigger)trigger;

22.  

23. if (trigger.getJobKey() == null) {

24. trig.setJobKey(jobDetail.getKey());

25. } else if (!trigger.getJobKey().equals(jobDetail.getKey())) {

26. throw new SchedulerException(

27. "Trigger does not reference given job!");

28. }

29.  

30. trig.validate();

31.  

32. Calendar cal = null;

33. if (trigger.getCalendarName() != null) {

34. cal = resources.getJobStore().retrieveCalendar(trigger.getCalendarName());

35. }

36. Date ft = trig.computeFirstFireTime(cal);

37.  

38. if (ft == null) {

39. throw new SchedulerException(

40. "Based on configured schedule, the given trigger '" + trigger.getKey() + "' will never fire.");

41. }

42.  

43. resources.getJobStore().storeJobAndTrigger(jobDetail, trig);

44. notifySchedulerListenersJobAdded(jobDetail);

45. notifySchedulerThread(trigger.getNextFireTime().getTime());

46. notifySchedulerListenersSchduled(trigger);

47.  

48. return ft;

49. }

     resources.getJobStore().storeJobAndTrigger(jobDetail, trig);是执行存储的语句。 

    resources是QuartzSchedulerResources的实例，此类中包含JobStore的实例，JobStore是专门用于存储job和trigger对象的接口。此处使用JobStoreSupport中的方法。JobStoreSupport实现了JobStore接口。 

1. public void storeJobAndTrigger(final JobDetail newJob,

2. final OperableTrigger newTrigger)

3. throws JobPersistenceException {

4. executeInLock(

5. (isLockOnInsert()) ? LOCK_TRIGGER_ACCESS : null,

6. new VoidTransactionCallback() {

7. public void executeVoid(Connection conn) throws JobPersistenceException {

8. storeJob(conn, newJob, false);

9. storeTrigger(conn, newTrigger, newJob, false,

10. Constants.STATE_WAITING, false, false);

11. }

12. });

13. }

   storeJob 和 storeTrigger方法使用sql语句插入任务信息。此处不再列出代码。

标签：quartz,job,trigger,SchedulerException,new,null,jobDetail
来源： https://blog.csdn.net/f45056231p/article/details/90204528