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精进Quartz源码—QuartzSchedulerThread.run() 源码分析(三)

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QuartzSchedulerThread.run()是主要处理任务的方法!下面进行分析,方便自己查看! 我都是分析的jobStore 方式为jdbc的SimpleTrigger!RAM的方式类似分析方式!

如还没有阅读过Quartz学习——scheduler.start()启动源码分析请先阅读这一篇!

QuartzSchedulerThread.run()主要是在有可用线程的时候获取需要执行Trigger并出触发进行任务的调度!


解释:

{0} : 表的前缀 ,如表qrtztrigger ,{0}== qrtz

{1} :quartz.properties 中配置的 org.quartz.scheduler.instanceName: myInstanceName ,{1} ==myInstanceName

1 、QuartzSchedulerThread.run()源码讲解

/**
 * <p>
 * The main processing loop of the <code>QuartzSchedulerThread</code>.
 * </p>
 */
@Override
public void run() {
 boolean lastAcquireFailed = false;
 while (!halted.get()) {
 try {
 // check if we're supposed to pause...
 //检查我们是否应该暂停...
 synchronized (sigLock) {
 while (paused && !halted.get()) {
 try {
 // wait until togglePause(false) is called...
 //等待直到togglePause(false)被调用... 
 sigLock.wait(1000L);
 } catch (InterruptedException ignore) {
 }
 }
 if (halted.get()) {
 break;
 }
 }
 //2.1获取可用线程的数量
 int availThreadCount = qsRsrcs.getThreadPool().blockForAvailableThreads();
 //将永远是true,由于blockForAvailableThreads的语义...
 if(availThreadCount > 0) { // will always be true, due to semantics of blockForAvailableThreads...
 List<OperableTrigger> triggers = null;//定义触发器集合
 long now = System.currentTimeMillis();//获取当前的时间
 clearSignaledSchedulingChange();
 try {
 //2.2 从jobStore中获取下次要触发的触发器集合
 //idleWaitTime == 30L * 1000L; 当调度程序发现没有当前触发器要触发,它应该等待多长时间再检查...
 triggers = qsRsrcs.getJobStore().acquireNextTriggers(
 now + idleWaitTime, Math.min(availThreadCount, qsRsrcs.getMaxBatchSize()), qsRsrcs.getBatchTimeWindow());
 lastAcquireFailed = false;
 if (log.isDebugEnabled()) 
 log.debug("batch acquisition of " + (triggers == null ? 0 : triggers.size()) + " triggers");
 } catch (JobPersistenceException jpe) {
 if(!lastAcquireFailed) {
 qs.notifySchedulerListenersError(
 "An error occurred while scanning for the next triggers to fire.",
 jpe);
 }
 lastAcquireFailed = true;
 continue;
 } catch (RuntimeException e) {
 if(!lastAcquireFailed) {
 getLog().error("quartzSchedulerThreadLoop: RuntimeException "
 +e.getMessage(), e);
 }
 lastAcquireFailed = true;
 continue;
 }
 //判断返回的触发器存在
 if (triggers != null && !triggers.isEmpty()) {
 now = System.currentTimeMillis();
 long triggerTime = triggers.get(0).getNextFireTime().getTime();
 //若有没有触发的Trigger,下次触发时间 next_fire_time 这个会在启动的时候有个默认的misfire机制,如上一篇中分析的 。setNextFireTime(); 即start()启动时候的当前时间。
 long timeUntilTrigger = triggerTime - now;
 while(timeUntilTrigger > 2) {//这里为什么是2 ???不懂???
 synchronized (sigLock) {
 if (halted.get()) {
 break;
 }
 if (!isCandidateNewTimeEarlierWithinReason(triggerTime, false)) {
 try {
 // we could have blocked a long while
 // on 'synchronize', so we must recompute
 now = System.currentTimeMillis();
 timeUntilTrigger = triggerTime - now;
 if(timeUntilTrigger >= 1)
 sigLock.wait(timeUntilTrigger);
 } catch (InterruptedException ignore) {
 }
 }
 }
 if(releaseIfScheduleChangedSignificantly(triggers, triggerTime)) {
 break;
 }
 now = System.currentTimeMillis();
 timeUntilTrigger = triggerTime - now;
 }
 // this happens if releaseIfScheduleChangedSignificantly decided to release triggers
 //这种情况发生,如果releaseIfScheduleChangedSignificantly 决定 释放Trigger
 if(triggers.isEmpty())
 continue;
 // set triggers to 'executing'
 //将触发器设置为“正在执行”
 List<TriggerFiredResult> bndles = new ArrayList<TriggerFiredResult>();
 boolean goAhead = true;
 synchronized(sigLock) {
 goAhead = !halted.get();
 }
 if(goAhead) {
 try {
 //2.3 通知JobStore调度程序现在正在触发其先前已获取(保留)的给定触发器(执行其关联的作业)。
 List<TriggerFiredResult> res = qsRsrcs.getJobStore().triggersFired(triggers);
 if(res != null)
 bndles = res; //下面的2.3方法返回的数据赋值到bndles
 } catch (SchedulerException se) {
 qs.notifySchedulerListenersError(
 "An error occurred while firing triggers '"
 + triggers + "'", se);
 //QTZ-179 : a problem occurred interacting with the triggers from the db
 //we release them and loop again
 for (int i = 0; i < triggers.size(); i++) {
 qsRsrcs.getJobStore().releaseAcquiredTrigger(triggers.get(i));
 }
 continue;
 }
 }
 //循环List<TriggerFiredResult> bndles 集合,获取TriggerFiredResult和TriggerFiredBundle等 
 for (int i = 0; i < bndles.size(); i++) {
 TriggerFiredResult result = bndles.get(i);
 TriggerFiredBundle bndle = result.getTriggerFiredBundle();
 Exception exception = result.getException();
 if (exception instanceof RuntimeException) {
 getLog().error("RuntimeException while firing trigger " + triggers.get(i), exception);
 qsRsrcs.getJobStore().releaseAcquiredTrigger(triggers.get(i));
 continue;
 }
 // it's possible to get 'null' if the triggers was paused,
 // blocked, or other similar occurrences that prevent it being
 // fired at this time... or if the scheduler was shutdown (halted)
 //如果触发器被暂停,阻塞或其他类似的事件阻止它在这时被触发,或者如果调度器被关闭(暂停),则可以获得'null'
 if (bndle == null) {
 qsRsrcs.getJobStore().releaseAcquiredTrigger(triggers.get(i));
 continue;
 }
 JobRunShell shell = null;
 try {
 //创建 JobRunShell ,并初始化
 shell = qsRsrcs.getJobRunShellFactory().createJobRunShell(bndle);
 shell.initialize(qs);
 } catch (SchedulerException se) {
 qsRsrcs.getJobStore().triggeredJobComplete(triggers.get(i), bndle.getJobDetail(), CompletedExecutionInstruction.SET_ALL_JOB_TRIGGERS_ERROR);
 continue;
 }
 if (qsRsrcs.getThreadPool().runInThread(shell) == false) {
 // this case should never happen, as it is indicative of the
 // scheduler being shutdown or a bug in the thread pool or
 // a thread pool being used concurrently - which the docs
 // say not to do...
 //这种情况不应该发生,因为它表示调度程序正在关闭或线程池或线程池中并发使用的错误 - 文档说不要这样做...
 getLog().error("ThreadPool.runInThread() return false!");
 qsRsrcs.getJobStore().triggeredJobComplete(triggers.get(i), bndle.getJobDetail(), CompletedExecutionInstruction.SET_ALL_JOB_TRIGGERS_ERROR);
 }
 }
 continue; // while (!halted)
 }
 } else { // if(availThreadCount > 0)
 // should never happen, if threadPool.blockForAvailableThreads() follows contract
 ////应该永远不会发生,如果threadPool.blockForAvailableThreads()遵循约定
 continue; // while (!halted)
 }
 long now = System.currentTimeMillis();
 long waitTime = now + getRandomizedIdleWaitTime();
 long timeUntilContinue = waitTime - now;
 //idleWaitTime == 30L * 1000L; idleWaitVariablness == 7 * 1000; 
 //计算getRandomizedIdleWaitTime()的值 : idleWaitTime - random.nextInt(idleWaitVariablness);
 synchronized(sigLock) {
 try {
 if(!halted.get()) {
 // QTZ-336 A job might have been completed in the mean time and we might have
 // missed the scheduled changed signal by not waiting for the notify() yet
 // Check that before waiting for too long in case this very job needs to be
 // scheduled very soon
 if (!isScheduleChanged()) {
 sigLock.wait(timeUntilContinue);
 }
 }
 } catch (InterruptedException ignore) {
 }
 }
 } catch(RuntimeException re) {
 getLog().error("Runtime error occurred in main trigger firing loop.", re);
 }
 } // while (!halted)
 // drop references to scheduler stuff to aid garbage collection...
 //删除对调度程序内容的引用以帮助垃圾回收...
 qs = null;
 qsRsrcs = null;
}

2.1获取可用线程的数量

// 参考 quartz2.2源码分析3-线程模型:https://my.oschina.net/chengxiaoyuan/blog/674603
//获取线程池,两个实现 SimpleThreadPool 和 ZeroSizeThreadPool, 一般使用SimpleThreadPool,在quartz.properties 中配置
public int blockForAvailableThreads() {//方法具体实现,没有可用线程等待。。。。
 synchronized(nextRunnableLock) {
 while((availWorkers.size() < 1 || handoffPending) && !isShutdown) {
 try {
 nextRunnableLock.wait(500);
 } catch (InterruptedException ignore) {
 }
 }
 return availWorkers.size();
 }
}

2.2 从jobStore中获取下次要触发的触发器集合

//acquireNextTriggers( now + idleWaitTime, Math.min(availThreadCount, qsRsrcs.getMaxBatchSize()), qsRsrcs.getBatchTimeWindow());
//获取要触发的下一个N个触发器的句柄,并由调用调度器将它们标记为“保留”。
//noLaterThan if > 0,那么JobStore应该只返回一个触发器,该触发器不会晚于此值中所表示的时间触发:
public List<OperableTrigger> acquireNextTriggers(final long noLaterThan, final int maxCount, final long timeWindow)
 throws JobPersistenceException {
 String lockName;
 //isAcquireTriggersWithinLock() false , maxCount == 1
 if(isAcquireTriggersWithinLock() || maxCount > 1) { 
 lockName = LOCK_TRIGGER_ACCESS;
 } else {
 lockName = null;
 }
 return executeInNonManagedTXLock(lockName, 
 new TransactionCallback<List<OperableTrigger>>() {
 public List<OperableTrigger> execute(Connection conn) throws JobPersistenceException {
 //2.2.1 到了这里,继续往下,这里返回需要下次执行的Trigger
 return acquireNextTrigger(conn, noLaterThan, maxCount, timeWindow);
 }
 },
 new TransactionValidator<List<OperableTrigger>>() {
 public Boolean validate(Connection conn, List<OperableTrigger> result) throws JobPersistenceException {
 try {
 //选择所有fired-trigger记录的状态
 List<FiredTriggerRecord> acquired = getDelegate().selectInstancesFiredTriggerRecords(conn, getInstanceId());
 Set<String> fireInstanceIds = new HashSet<String>();
 for (FiredTriggerRecord ft : acquired) {
 fireInstanceIds.add(ft.getFireInstanceId());
 }
 for (OperableTrigger tr : result) {
 if (fireInstanceIds.contains(tr.getFireInstanceId())) {
 return true;
 }
 }
 return false;
 } catch (SQLException e) {
 throw new JobPersistenceException("error validating trigger acquisition", e);
 }
 }
 });
}

2.2.1看 acquireNextTrigger方法

protected List<OperableTrigger> acquireNextTrigger(Connection conn, long noLaterThan, int maxCount, long timeWindow)
 throws JobPersistenceException {
 if (timeWindow < 0) {
 throw new IllegalArgumentException();
 }
 List<OperableTrigger> acquiredTriggers = new ArrayList<OperableTrigger>();
 Set<JobKey> acquiredJobKeysForNoConcurrentExec = new HashSet<JobKey>();
 final int MAX_DO_LOOP_RETRY = 3;
 int currentLoopCount = 0;
 long firstAcquiredTriggerFireTime = 0;
 do {
 currentLoopCount ++;
 try {
 //2.2.2查询下次触发的触发器 Triggerkey ,在继续看这个方法里面
 List<TriggerKey> keys = getDelegate().selectTriggerToAcquire(conn, noLaterThan + timeWindow, getMisfireTime(), maxCount);
 // No trigger is ready to fire yet.
 //还没有触发器准备好。 keys 为上面查询出来的!!!
 if (keys == null || keys.size() == 0)
 return acquiredTriggers;
 //循环TriggerKey name 和 group
 for(TriggerKey triggerKey: keys) {
 //如果我们的触发器不再可用,请尝试一个新的触发器。 (retrieve:检索)
 OperableTrigger nextTrigger = retrieveTrigger(conn, triggerKey);
 //查询Trigger 并封装!retrieveTrigger 的 sql
 "SELECT * FROM {0}TRIGGERS WHERE SCHED_NAME = {1} AND TRIGGER_NAME = ? AND TRIGGER_GROUP = ?"
 if(nextTrigger == null) {
 continue; // next trigger
 }
 //如果触发器的作业设置为@DisallowConcurrentExecution,并且它已经添加到结果中,则将其放回到timeTriggers设置并继续搜索下
 //一个触发器。
 JobKey jobKey = nextTrigger.getJobKey();
 //为给定的作业名称/组名称选择JobDetail对象。 封装成JobDetailImpl 对象
 JobDetail job = getDelegate().selectJobDetail(conn, jobKey, getClassLoadHelper());
 //selectJobDetail 的sql :"SELECT * FROM {0}JOB_DETAILS WHERE SCHED_NAME = {1} AND JOB_NAME = ? AND JOB_GROUP = ?"
 if (job.isConcurrentExectionDisallowed()) {//相关联的Job类是否携带DisallowConcurrentExecution注释。
 if (acquiredJobKeysForNoConcurrentExec.contains(jobKey)) {
 continue; // next trigger
 } else {
 acquiredJobKeysForNoConcurrentExec.add(jobKey);
 }
 }
 // We now have a acquired trigger, let's add to return list.
 // If our trigger was no longer in the expected state, try a new one.
 //我们现在有一个获取触发器,让我们添加到返回列表。 如果我们的触发器不再处于预期状态,请尝试新的触发器。
 int rowsUpdated = getDelegate().updateTriggerStateFromOtherState(conn, triggerKey, STATE_ACQUIRED, STATE_WAITING);
 //updateTriggerStateFromOtherState 如果给定触发器处于给定的旧状态,则将其更新为给定的新状态
 //第一个? newState ; 第四个 ? oldState updateTriggerStateFromOtherState的sql
 "UPDATE {0}TRIGGERS SET TRIGGER_STATE = ? WHERE SCHED_NAME = {1} AND TRIGGER_NAME = ? AND TRIGGER_GROUP = ? AND TRIGGER_STATE = ?"
 if (rowsUpdated <= 0) {
 continue; // next trigger
 }
 nextTrigger.setFireInstanceId(getFiredTriggerRecordId());
 //插入一个fired Trigger, 更新当前执行的时间(FIRED_TIME)和下次要执行的时间(SCHED_TIME)
 //如下看详情请查看源码的这个方法 以及执行的sql,主要代码如下注释:
 /**
 "INSERT INTO {0}FIRED_TRIGGERS (SCHED_NAME, ENTRY_ID, TRIGGER_NAME, TRIGGER_GROUP, INSTANCE_NAME, FIRED_TIME, SCHED_TIME, STATE, JOB_NAME, JOB_GROUP, IS_NONCONCURRENT, REQUESTS_RECOVERY, PRIORITY) VALUES({1}, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)"
 //FIRED_TIME
 ps.setBigDecimal(5, new BigDecimal(String.valueOf(System.currentTimeMillis())));
 //SCHED_TIME
 ps.setBigDecimal(6, new BigDecimal(String.valueOf(trigger.getNextFireTime().getTime())));
 */
 getDelegate().insertFiredTrigger(conn, nextTrigger, STATE_ACQUIRED, null);
 //下次执行的Trigger放入acquiredTriggers List中 
 acquiredTriggers.add(nextTrigger);
 if(firstAcquiredTriggerFireTime == 0)
 firstAcquiredTriggerFireTime = nextTrigger.getNextFireTime().getTime();
 }
 // if we didn't end up with any trigger to fire from that first
 // batch, try again for another batch. We allow with a max retry count.
 if(acquiredTriggers.size() == 0 && currentLoopCount < MAX_DO_LOOP_RETRY) {
 continue;
 }
 // We are done with the while loop.
 break;
 } catch (Exception e) {
 throw new JobPersistenceException(
 "Couldn't acquire next trigger: " + e.getMessage(), e);
 }
 } while (true);
 // Return the acquired trigger list
 //返回获取的触发器列表
 return acquiredTriggers; 
} 
}

2.2.2查询下次触发的触发器 selectTriggerToAcquire

/**
选择下一次需要触发器的Trigger,它将在两个给定时间戳之间按照触发时间的升序触发,然后按优先级降序。
*参数:
 conn数据库Connection
 noLaterThan触发器的getNextFireTime()的最大值(独占)
 noEarlierThan触发器的最大值getMisfireTime()
 maxCount允许在返回列表中获取的最大触发器数量。
备注:
noLaterThan : System.currentTimeMillis() + 30*1000L(30秒)
noEarlierThan :System.currentTimeMillis() + 60*1000L(one minute:一分钟)
*/
 selectTriggerToAcquire(Connection conn, long noLaterThan, long noEarlierThan, int maxCount)
 最终这个方法执行的sql:
 "SELECT TRIGGER_NAME, TRIGGER_GROUP, NEXT_FIRE_TIME, PRIORITY FROM {0}TRIGGERS WHERE SCHED_NAME = {1} AND TRIGGER_STATE = ? AND NEXT_FIRE_TIME <= ? AND (MISFIRE_INSTR = -1 OR (MISFIRE_INSTR != -1 AND NEXT_FIRE_TIME >= ?)) ORDER BY NEXT_FIRE_TIME ASC, PRIORITY DESC"
//搜索出下次需要执行的Trigger
//NEXT_FIRE_TIME <= ?(noLaterThan) and NEXT_FIRE_TIME >= ?(noEarlierThan) noEarlierThan <= 下次触发的时间 <= noLaterThan

注:这里的sql和MISFIREINSTR 这个值有关系,默认情况MISFIREINSTR = 0;除非你自己设置的MISFIRE处理机制! 这个地方要想弄明白,需要去了解Quartz源码——Quartz调度器的Misfire处理规则(四)——scheduler.start()启动源码分析(二)中2.1 恢复job recoverJobs(); 中讲解代码!

我测试执行的一条sql:

 com.mysql.jdbc.JDBC4PreparedStatement@72163468: 
"SELECT TRIGGER_NAME, TRIGGER_GROUP, NEXT_FIRE_TIME, PRIORITY FROM qrtz_TRIGGERS WHERE SCHED_NAME = 'dufy_test' AND TRIGGER_STATE = 'WAITING' AND NEXT_FIRE_TIME <= 1481126708931 AND (MISFIRE_INSTR = -1 OR (MISFIRE_INSTR != -1 AND NEXT_FIRE_TIME >= 1481126618934)) ORDER BY NEXT_FIRE_TIME ASC, PRIORITY DESC"
重点这里:(MISFIRE_INSTR = -1 OR (MISFIRE_INSTR != -1 AND NEXT_FIRE_TIME >= 1481126618934))

提个小小问题, 什么情况MISFIRE_INSTR == -1 ???

2.3 通知JobStore调度程序现在正在触发其先前已获取(保留)的给定触发器(执行其关联的作业)。

public List<TriggerFiredResult> triggersFired(final List<OperableTrigger> triggers) throws JobPersistenceException {
 return executeInNonManagedTXLock(LOCK_TRIGGER_ACCESS,
 new TransactionCallback<List<TriggerFiredResult>>() {
 public List<TriggerFiredResult> execute(Connection conn) throws JobPersistenceException {
 List<TriggerFiredResult> results = new ArrayList<TriggerFiredResult>();
 TriggerFiredResult result;
 for (OperableTrigger trigger : triggers) {
 try {
 TriggerFiredBundle bundle = triggerFired(conn, trigger);//这个里面比较复杂,分析!!!
 //然后封装成TriggerFiredResult 返回, 回到2.3开始的地方run方法中!
 result = new TriggerFiredResult(bundle);
 } catch (JobPersistenceException jpe) {
 result = new TriggerFiredResult(jpe);
 } catch(RuntimeException re) {
 result = new TriggerFiredResult(re);
 }
 results.add(result);
 }
 return results;
 }
 },
 new TransactionValidator<List<TriggerFiredResult>>() {
 ....
 });
}
protected TriggerFiredBundle triggerFired(Connection conn,
 OperableTrigger trigger)
 throws JobPersistenceException {
 JobDetail job;
 Calendar cal = null;
 // Make sure trigger wasn't deleted, paused, or completed...
 //确保触发器未被删除,暂停或完成...
 try { // if trigger was deleted, state will be STATE_DELETED
 //如果触发器被删除,状态将是STATE_DELETED
 String state = getDelegate().selectTriggerState(conn,
 trigger.getKey());
 //查询到数据,返回查询到的当前状态,否则返回 STATE_DELETED ,删除状态
 //sql:"SELECT TRIGGER_STATE FROM {0}TRIGGERS WHERE SCHED_NAME = {1} AND TRIGGER_NAME = ? AND TRIGGER_GROUP = ?"
 if (!state.equals(STATE_ACQUIRED)) {
 return null;
 }
 } catch (SQLException e) {
 throw new JobPersistenceException("Couldn't select trigger state: "
 + e.getMessage(), e);
 }
 try {
 //恢复job,根据 trigger.getJobKey() 获取Job的name 和 group
 job = retrieveJob(conn, trigger.getJobKey());
 //sql:"SELECT * FROM {0}JOB_DETAILS WHERE SCHED_NAME = {1} AND JOB_NAME = ? AND JOB_GROUP = ?"
 if (job == null) { return null; }
 } catch (JobPersistenceException jpe) {
 try {
 getLog().error("Error retrieving job, setting trigger state to ERROR.", jpe);
 getDelegate().updateTriggerState(conn, trigger.getKey(),
 STATE_ERROR);
 } catch (SQLException sqle) {
 getLog().error("Unable to set trigger state to ERROR.", sqle);
 }
 throw jpe;
 }
 // trigger 有CalendarName 去查询qrtz_calendar 表
 if (trigger.getCalendarName() != null) {
 cal = retrieveCalendar(conn, trigger.getCalendarName());
 //sql: "SELECT * FROM {0}CALENDARS WHERE SCHED_NAME = {1} AND CALENDAR_NAME = ?"
 if (cal == null) { return null; }
 }
 try {
 //更新触发的触发器记录。 将更新字段“触发实例”,“触发时间”和“状态”。STATE_EXECUTING:执行状态
 getDelegate().updateFiredTrigger(conn, trigger, STATE_EXECUTING, job);
 //sql:"UPDATE {0}FIRED_TRIGGERS SET INSTANCE_NAME = ?, FIRED_TIME = ?, SCHED_TIME = ?, STATE = ?, JOB_NAME = ?, JOB_GROUP = ?, IS_NONCONCURRENT = ?, REQUESTS_RECOVERY = ? WHERE SCHED_NAME = {1} AND ENTRY_ID = ?"
 //ps.setBigDecimal(2, new BigDecimal(String.valueOf(System.currentTimeMillis())));
 //ps.setBigDecimal(3, new BigDecimal(String.valueOf(trigger.getNextFireTime().getTime())));
 } catch (SQLException e) {
 throw new JobPersistenceException("Couldn't insert fired trigger: "
 + e.getMessage(), e);
 }
 Date prevFireTime = trigger.getPreviousFireTime();
 // call triggered - to update the trigger's next-fire-time state...
 // 2.3.1 更新触发器的下一个触发时间状态...
 trigger.triggered(cal);
 String state = STATE_WAITING;
 boolean force = true;
 //相关联的Job类是否携带DisallowConcurrentExecution注释。
 if (job.isConcurrentExectionDisallowed()) {
 state = STATE_BLOCKED;
 force = false;
 try {
 getDelegate().updateTriggerStatesForJobFromOtherState(conn, job.getKey(),
 STATE_BLOCKED, STATE_WAITING);
 getDelegate().updateTriggerStatesForJobFromOtherState(conn, job.getKey(),
 STATE_BLOCKED, STATE_ACQUIRED);
 getDelegate().updateTriggerStatesForJobFromOtherState(conn, job.getKey(),
 STATE_PAUSED_BLOCKED, STATE_PAUSED);
 } catch (SQLException e) {
 throw new JobPersistenceException(
 "Couldn't update states of blocked triggers: "
 + e.getMessage(), e);
 }
 } 
 //getNextFireTime == null 说明trigger执行完成,没有下次触发的时间了
 if (trigger.getNextFireTime() == null) {
 state = STATE_COMPLETE;
 force = true;
 }
 //2.3.2插入或者更新一个Trigger ,进入看看
 storeTrigger(conn, trigger, job, true, state, force, false);
 //清除'dirty'标志(将dirty标志设置为false)。
 job.getJobDataMap().clearDirtyFlag();
 //创建一个 TriggerFiredBundle的对象,封装数据
 return new TriggerFiredBundle(job, trigger, cal, trigger.getKey().getGroup()
 .equals(Scheduler.DEFAULT_RECOVERY_GROUP), new Date(), trigger
 .getPreviousFireTime(), prevFireTime, trigger.getNextFireTime());
}

2.3.1 更新触发器的下一个触发时间状态…

//当调度程序决定“触发”触发器(执行关联的作业)时调用,以便为触发器更新自身以进行下一次触发(如果有)。 
public void triggered(Calendar calendar) {
 timesTriggered++; //默认 timesTriggered==0
 previousFireTime = nextFireTime; //下次执行的next_time赋值给pre_time
 nextFireTime = getFireTimeAfter(nextFireTime);//获取下次触发的时间
 while (nextFireTime != null && calendar != null
 && !calendar.isTimeIncluded(nextFireTime.getTime())) {
 nextFireTime = getFireTimeAfter(nextFireTime);
 if(nextFireTime == null)
 break;
 //avoid infinite loop
 java.util.Calendar c = java.util.Calendar.getInstance();
 c.setTime(nextFireTime);
 if (c.get(java.util.Calendar.YEAR) > YEAR_TO_GIVEUP_SCHEDULING_AT) {
 nextFireTime = null;
 }
 }
}

2.3.2插入或者更新一个Trigger ,进入看看

protected void storeTrigger(Connection conn,
 OperableTrigger newTrigger, JobDetail job, boolean replaceExisting, String state,
 boolean forceState, boolean recovering)
 throws JobPersistenceException {
 //检查Trigger是否存在 , trigger 的name 和 group
 boolean existingTrigger = triggerExists(conn, newTrigger.getKey());
 if ((existingTrigger) && (!replaceExisting)) { 
 throw new ObjectAlreadyExistsException(newTrigger); 
 }
 try {
 boolean shouldBepaused;
 if (!forceState) {
 shouldBepaused = getDelegate().isTriggerGroupPaused(
 conn, newTrigger.getKey().getGroup());
 if(!shouldBepaused) {
 shouldBepaused = getDelegate().isTriggerGroupPaused(conn,
 ALL_GROUPS_PAUSED);
 if (shouldBepaused) {
 getDelegate().insertPausedTriggerGroup(conn, newTrigger.getKey().getGroup());
 }
 }
 if (shouldBepaused && (state.equals(STATE_WAITING) || state.equals(STATE_ACQUIRED))) {
 state = STATE_PAUSED;
 }
 }
 //job 为null ,重新去查询一遍 jobDetail 根据 Trigger的name和group
 if(job == null) {
 job = getDelegate().selectJobDetail(conn, newTrigger.getJobKey(), getClassLoadHelper());
 }
 if (job == null) {
 throw new JobPersistenceException("The job ("
 + newTrigger.getJobKey()
 + ") referenced by the trigger does not exist.");
 }
 //是否有注解 ,上面传过来的recovering参数 == false
 if (job.isConcurrentExectionDisallowed() && !recovering) { 
 state = checkBlockedState(conn, job.getKey(), state);
 }
 //existingTrigger存在的话,进行更新操作,否则插入操作
 if (existingTrigger) {
 //2.3.2.1这个里面还是很复杂,贴代码出来了 getDelegate().updateTrigger(conn, newTrigger, state, job);
 getDelegate().updateTrigger(conn, newTrigger, state, job);
 } else {
 //插入和更新很多类似地方 具体代码不贴出来了 !
 getDelegate().insertTrigger(conn, newTrigger, state, job);
 }
 } catch (Exception e) {
 throw new JobPersistenceException("Couldn't store trigger '" + newTrigger.getKey() + "' for '" 
 + newTrigger.getJobKey() + "' job:" + e.getMessage(), e);
 }
}

2.3.2.1这个里面还是很复杂,贴代码出来了

//更新基本触发器数据。
public int updateTrigger(Connection conn, OperableTrigger trigger, String state,
 JobDetail jobDetail) throws SQLException, IOException {
 // save some clock cycles by unnecessarily writing job data blob ...
 //通过不必要地写入作业数据blob来保存一些时钟周期...
 boolean updateJobData = trigger.getJobDataMap().isDirty();//确定Map是否标记为dirty。
 ByteArrayOutputStream baos = null;
 if(updateJobData && trigger.getJobDataMap().size() > 0) {
 baos = serializeJobData(trigger.getJobDataMap());
 }
 PreparedStatement ps = null;
 int insertResult = 0;
 try {
 if(updateJobData) {
 ps = conn.prepareStatement(rtp(UPDATE_TRIGGER));
 ---------------------------------------------------------------------
 "UPDATE {0}TRIGGERS SET JOB_NAME = ?, JOB_GROUP = ?, DESCRIPTION = ?, NEXT_FIRE_TIME = ?, PREV_FIRE_TIME = ?, TRIGGER_STATE = ?, TRIGGER_TYPE = ?, START_TIME = ?, END_TIME = ?, CALENDAR_NAME = ?, MISFIRE_INSTR = ?, PRIORITY = ?, JOB_DATA = ? WHERE SCHED_NAME = {1} AND TRIGGER_NAME = ? AND TRIGGER_GROUP = ?"
 ---------------------------------------------------------------------
 } else {
 ps = conn.prepareStatement(rtp(UPDATE_TRIGGER_SKIP_DATA));
 ---------------------------------------------------------------------
 "UPDATE {0}TRIGGERS SET JOB_NAME = ?, JOB_GROUP = ?, DESCRIPTION = ?, NEXT_FIRE_TIME = ?, PREV_FIRE_TIME = ?, TRIGGER_STATE = ?, TRIGGER_TYPE = ?, START_TIME = ?, END_TIME = ?, CALENDAR_NAME = ?, MISFIRE_INSTR = ?, PRIORITY = ? WHERE SCHED_NAME = {1} AND TRIGGER_NAME = ? AND TRIGGER_GROUP = ?"
 ---------------------------------------------------------------------
 }
 ps.setString(1, trigger.getJobKey().getName());
 ps.setString(2, trigger.getJobKey().getGroup());
 ps.setString(3, trigger.getDescription());
 long nextFireTime = -1;
 if (trigger.getNextFireTime() != null) {//触发器下次执行的时间不为null
 //备注:一般执行完成,即是complete 状态,getNextFireTime == null
 nextFireTime = trigger.getNextFireTime().getTime();
 }
 ps.setBigDecimal(4, new BigDecimal(String.valueOf(nextFireTime)));
 long prevFireTime = -1;
 if (trigger.getPreviousFireTime() != null) {//触发器之前执行的时间不为 null
 //备注:触发器第一次执行的时候 getNextFireTime 为 null
 prevFireTime = trigger.getPreviousFireTime().getTime();
 }
 ps.setBigDecimal(5, new BigDecimal(String.valueOf(prevFireTime)));
 ps.setString(6, state);
 //获取对于代理 ;如JDBC 或者RAM
 TriggerPersistenceDelegate tDel = findTriggerPersistenceDelegate(trigger);
 String type = TTYPE_BLOB;
 if(tDel != null)
 type = tDel.getHandledTriggerTypeDiscriminator();
 ps.setString(7, type);
 ps.setBigDecimal(8, new BigDecimal(String.valueOf(trigger
 .getStartTime().getTime())));
 long endTime = 0;
 if (trigger.getEndTime() != null) {
 endTime = trigger.getEndTime().getTime();
 }
 ps.setBigDecimal(9, new BigDecimal(String.valueOf(endTime)));
 ps.setString(10, trigger.getCalendarName());
 ps.setInt(11, trigger.getMisfireInstruction());
 ps.setInt(12, trigger.getPriority());
 if(updateJobData) {
 setBytes(ps, 13, baos);
 ps.setString(14, trigger.getKey().getName());
 ps.setString(15, trigger.getKey().getGroup());
 } else {
 ps.setString(13, trigger.getKey().getName());
 ps.setString(14, trigger.getKey().getGroup());
 }
 insertResult = ps.executeUpdate();
 if(tDel == null)
 updateBlobTrigger(conn, trigger);
 else
 //更新扩展触发器属性
 tDel.updateExtendedTriggerProperties(conn, trigger, state, jobDetail);
 ---------------------------------------------------------------
 "UPDATE {0}SIMPLE_TRIGGERS SET REPEAT_COUNT = ?, REPEAT_INTERVAL = ?, TIMES_TRIGGERED = ? WHERE SCHED_NAME = {1} AND TRIGGER_NAME = ? AND TRIGGER_GROUP = ?"
 ---------------------------------------------------------------------
 } finally {
 closeStatement(ps);
 }
 return insertResult;//返回执行的结果 为int 
}

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