Quartz源码——scheduler.start()启动源码分析（二）

scheduler.start()是Quartz的启动方式！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！

Quartz学习——QuartzSchedulerThread.run 源码分析：http://blog.csdn.net/u010648555/article/details/53525041

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解释：

{0} ： 表的前缀 ，如表qrtz_trigger ,{0}== qrtz_

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

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Quartz 的启动要调用start()方法进行线程的启动，并执行需要出发的Trigger，start方法里面进行的操作：

1. 启动的初始化
2. 判断是否集群，对应不同的操作
3. 若是非集群，首先有恢复机制，恢复任何失败或misfire的作业，并根据需要清理数据存储。
4. 初始化线程管理，唤醒所有等待的线程！

下面就是简单的源码分析：

1.QuartzScheduler.start();

public void start() throws SchedulerException {

        if (shuttingDown|| closed) {
            throw new SchedulerException(
                    "The Scheduler cannot be restarted after shutdown() has been called.");
        }

        // QTZ-212 : calling new schedulerStarting() method on the listeners
        // right after entering start()
        notifySchedulerListenersStarting();

        if (initialStart == null) {//初始化标识为null，进行初始化操作
            initialStart = new Date();
            this.resources.getJobStore().schedulerStarted();//1.1 主要分析的地方
            startPlugins();
        } else {

            resources.getJobStore().schedulerResumed();//1.2如果已经初始化过，则恢复jobStore
        }

        schedThread.togglePause(false);//3.1 唤醒所有等待的线程

        getLog().info(
                "Scheduler " + resources.getUniqueIdentifier() + " started.");

        notifySchedulerListenersStarted();
    }

1.1 this.resources.getJobStore().schedulerStarted();//主要分析的地方

public void schedulerStarted() throws SchedulerException {
		//是集群
        if (isClustered()) {
            clusterManagementThread = new ClusterManager();
            if(initializersLoader != null)
                clusterManagementThread.setContextClassLoader(initializersLoader);
            clusterManagementThread.initialize();
        } else {//不是集群
            try {
                recoverJobs();//2.1 恢复job
            } catch (SchedulerException se) {
                throw new SchedulerConfigException(
                        "Failure occured during job recovery.", se);
            }
        }

        misfireHandler = new MisfireHandler();
        if(initializersLoader != null)
            misfireHandler.setContextClassLoader(initializersLoader);
        misfireHandler.initialize();//2.2 获取ThreadExecutor 线程管理
        schedulerRunning = true;

        getLog().debug("JobStore background threads started (as scheduler was started).");
    }

1.2如果已经初始化过，则恢复调度器运行 resources.getJobStore().schedulerResumed();

 private volatile boolean schedulerRunning = false;//默认schedulerRunning = false
 public void schedulerResumed() {
        schedulerRunning = true;
    }

2.1 恢复job recoverJobs();

//启动的时候 有一个恢复机制：
	//recoverJobs -----  将恢复任何失败或misfire的作业，并根据需要清理数据存储。
	 protected void recoverJobs() throws JobPersistenceException {
        executeInNonManagedTXLock(
            LOCK_TRIGGER_ACCESS,
            new VoidTransactionCallback() {
                public void executeVoid(Connection conn) throws JobPersistenceException {
                    recoverJobs(conn);//恢复job
                }
            }, null);
    }

	protected void recoverJobs(Connection conn) throws JobPersistenceException {
        try {
            （1）//更新不一致的作业状态  	先修改状态，将 ACQUIRED 和 BLOCKED ---> WAITING
            int rows = getDelegate().updateTriggerStatesFromOtherStates(conn,
                    STATE_WAITING, STATE_ACQUIRED, STATE_BLOCKED);

            rows += getDelegate().updateTriggerStatesFromOtherStates(conn,
                        STATE_PAUSED, STATE_PAUSED_BLOCKED, STATE_PAUSED_BLOCKED);

			//----更新sql---
			//"UPDATE {0}TRIGGERS SET TRIGGER_STATE = ? WHERE SCHED_NAME = {1} AND (TRIGGER_STATE = ? OR TRIGGER_STATE = ?)"

            getLog().info(
                    "Freed " + rows
                            + " triggers from 'acquired' / 'blocked' state.");

            // clean up misfired jobs
			//2.1.1 清理misfire的jobs
            recoverMisfiredJobs(conn, true);

            // recover jobs marked for recovery that were not fully executed
			//2.1.2 恢复未完全执行的标记为恢复的作业 --查询 qrtz_fire_trigger
            List<OperableTrigger> recoveringJobTriggers = getDelegate()
                    .selectTriggersForRecoveringJobs(conn);
            getLog()
                    .info(
                            "Recovering "
                                    + recoveringJobTriggers.size()
                                    + " jobs that were in-progress at the time of the last shut-down.");

            for (OperableTrigger recoveringJobTrigger: recoveringJobTriggers) {
                if (jobExists(conn, recoveringJobTrigger.getJobKey())) {
                    recoveringJobTrigger.computeFirstFireTime(null);
                    storeTrigger(conn, recoveringJobTrigger, null, false,
                            STATE_WAITING, false, true);
                }
            }
            getLog().info("Recovery complete.");

            // remove lingering 'complete' triggers...
			//2.1.3 移除state == complete
            List<TriggerKey> cts = getDelegate().selectTriggersInState(conn, STATE_COMPLETE);
            for(TriggerKey ct: cts) {
                removeTrigger(conn, ct);
            }
            getLog().info(
                "Removed " + cts.size() + " 'complete' triggers.");

            // clean up any fired trigger entries
			//2.1.4 清理任何已触发的触发器条目
            int n = getDelegate().deleteFiredTriggers(conn);
            getLog().info("Removed " + n + " stale fired job entries.");
        } catch (JobPersistenceException e) {
            throw e;
        } catch (Exception e) {
            throw new JobPersistenceException("Couldn't recover jobs: "
                    + e.getMessage(), e);
        }
    }

2.1.1 清理misfire的jobs recoverMisfiredJobs(conn, true);

	//是否有misfire的Trigger
		//我们必须仍然寻找MISFIRED状态，以防触发器被遗忘
		//在此状态下升级到此版本不支持
	（a1）hasMisfiredTriggersInState(conn, STATE_WAITING, getMisfireTime(),
		maxMisfiresToHandleAtATime, misfiredTriggers);
		////getMisfireTime() 当前时间 -(减去) 一分钟 ,maxMisfiresToHandleAtATime == -1   ,misfiredTriggers== null 

		"SELECT TRIGGER_NAME, TRIGGER_GROUP FROM {0}TRIGGERS WHERE SCHED_NAME = {1} AND NOT (MISFIRE_INSTR = -1) AND NEXT_FIRE_TIME < ? AND TRIGGER_STATE = ? ORDER BY NEXT_FIRE_TIME ASC, PRIORITY DESC"

		上面sql查询出来结果是个list
				(aa1)若resultList.size() == count 返回 TRUE！！ 否则 返回false！
				(aa2)不等于 count ，封装数据，到resultList中，triggername  TriggerGroup

		//查询出来有misfire 的 Trigger
	（b2） misfiredTriggers.size() > 0
		 (bb1)输出日志信息   ：getLog().info(
		"Handling " + misfiredTriggers.size() +
			" trigger(s) that missed their scheduled fire-time.");

		（bb2）循环 misfiredTriggers List集合
			for (TriggerKey triggerKey: misfiredTriggers) {
				//retrieveTrigger ，检索Trigger，检索到进行数据封装
				OperableTrigger trig =
					retrieveTrigger(conn, triggerKey);
					 //retrieveTrigger 执行的操作
					（1）"SELECT * FROM {0}TRIGGERS WHERE SCHED_NAME = {1} AND TRIGGER_NAME = ? AND TRIGGER_GROUP = ?"
					（2）关联Trigger对应的类型，如simpleTrigger等

				if (trig == null) {
					continue;
				}

				//do 更新misfire的触发器
				doUpdateOfMisfiredTrigger(conn, trig, false, STATE_WAITING, recovering); //recovering===TRUE
					（1）cal = retrieveCalendar(conn, trig.getCalendarName()); 搞这个表，qrtz_calendar
					（2）trig.updateAfterMisfire(cal); //simpleTrigger默认的misfire 机制
						 setNextFireTime(new Date()); //设置下次执行的时间（next_fire_time）为当前时间！这里比较重要！！！
					（3） getNextFireTime != null
						 if (trig.getNextFireTime() == null) {
							storeTrigger(conn, trig,
								null, true, STATE_COMPLETE, forceState, recovering);
							schedSignaler.notifySchedulerListenersFinalized(trig);
						} else {
							storeTrigger(conn, trig, null, true, newStateIfNotComplete,
									forceState, false);

							// job == null  replaceExisting ==true  state==waitting   forceState==false  recovering==false
							storeTrigger(Connection conn,
								OperableTrigger newTrigger, JobDetail job, boolean replaceExisting, String state,
								boolean forceState, boolean recovering)

								//Insert or update a trigger.
							   boolean existingTrigger = triggerExists(conn, newTrigger.getKey());
								if (existingTrigger) {

									//state == waitting
									getDelegate().updateTrigger(conn, newTrigger, state, job);

									//更新sql
									/*
									"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 = ?"*/

								} else {
									getDelegate().insertTrigger(conn, newTrigger, state, job);
									//插入sql
									/*"INSERT INTO {0}TRIGGERS (SCHED_NAME, TRIGGER_NAME, TRIGGER_GROUP, JOB_NAME, JOB_GROUP, DESCRIPTION, NEXT_FIRE_TIME, PREV_FIRE_TIME, TRIGGER_STATE, TRIGGER_TYPE, START_TIME, END_TIME, CALENDAR_NAME, MISFIRE_INSTR, JOB_DATA, PRIORITY)  VALUES({1}, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)"*/
								}
						}

	（c3） long earliestNewTime = Long.MAX_VALUE; // long earliestNewTime = Long.MAX_VALUE; === 9223372036854775807
		  if(trig.getNextFireTime() != null && trig.getNextFireTime().getTime() < earliestNewTime){
				earliestNewTime = trig.getNextFireTime().getTime();
		  }

2.1.2 恢复未完全执行的标记为恢复的作业

List<OperableTrigger> recoveringJobTriggers = getDelegate()
                    .selectTriggersForRecoveringJobs(conn);
		// INSTANCE_NAME == dufy_test    REQUESTS_RECOVERY == true  实际封装到数据库查询是 REQUESTS_RECOVERY== 1
		"SELECT * FROM {0}FIRED_TRIGGERS WHERE SCHED_NAME = {1} AND INSTANCE_NAME = ? AND REQUESTS_RECOVERY = ?"
		//具体怎么是 truｅ是怎么转换成为 1的见附1图片！

	Recovery complete.恢复完成！！

2.1.3 移除state == complete

List<TriggerKey> cts = getDelegate().selectTriggersInState(conn, STATE_COMPLETE);
-----------------------------------------------------------------------------
"SELECT TRIGGER_NAME, TRIGGER_GROUP FROM {0}TRIGGERS WHERE SCHED_NAME = {1} AND TRIGGER_STATE = ?"
-----------------------------------------------------------------------------
for(TriggerKey ct: cts) {
	removeTrigger(conn, ct);
	---------------------------------------------------------------------
		（a）删除前，先查询jobDetail
			  JobDetail job = getDelegate().selectJobForTrigger(conn,getClassLoadHelper(), key, false);
				"SELECT J.JOB_NAME, J.JOB_GROUP, J.IS_DURABLE, J.JOB_CLASS_NAME, J.REQUESTS_RECOVERY FROM {0}TRIGGERS T, {0}JOB_DETAILS J WHERE T.SCHED_NAME = {1} AND J.SCHED_NAME = {1} AND T.TRIGGER_NAME = ? AND T.TRIGGER_GROUP = ? AND T.JOB_NAME = J.JOB_NAME AND T.JOB_GROUP = J.JOB_GROUP"

		（b）删除触发器，其侦听器及其Simple / Cron / BLOB子表条目。
		  boolean removedTrigger = deleteTriggerAndChildren(conn, key);
			 deleteTrigger(Connection conn, TriggerKey triggerKey)
			（b1）deleteTriggerExtension
				   "DELETE FROM {0}SIMPLE_TRIGGERS WHERE SCHED_NAME = {1} AND TRIGGER_NAME = ? AND TRIGGER_GROUP = ?"
				   "DELETE FROM {0}BLOB_TRIGGERS WHERE SCHED_NAME = {1} AND TRIGGER_NAME = ? AND TRIGGER_GROUP = ?"

			（b2）"DELETE FROM {0}TRIGGERS WHERE SCHED_NAME = {1} AND TRIGGER_NAME = ? AND TRIGGER_GROUP = ?"

		（c）是否删除jobdetail ，判断 isDurable 默认 为false。
			if (null != job && !job.isDurable()) {
				int numTriggers = getDelegate().selectNumTriggersForJob(conn,
						job.getKey());
				---------------------------------------------------------
				"SELECT COUNT(TRIGGER_NAME) FROM {0}TRIGGERS WHERE SCHED_NAME = {1} AND JOB_NAME = ? AND JOB_GROUP = ?"
				---------------------------------------------------------
				if (numTriggers == 0) {
					// Don't call removeJob() because we don't want to check for
					// triggers again.
					//不要调用removeJob（），因为我们不想再次检查触发器。
					deleteJobAndChildren(conn, job.getKey()); //删除作业及其侦听器。
					-----------------------------------------------------
					//deleteJobDetail(Connection conn, JobKey jobKey) 删除给定作业的作业明细记录。
					"DELETE FROM {0}JOB_DETAILS WHERE SCHED_NAME = {1} AND JOB_NAME = ? AND JOB_GROUP = ?"
					-----------------------------------------------------
				}
			}
	}

2.1.4 清理任何已触发的触发器条目

 int n = getDelegate().deleteFiredTriggers(conn);
 ----------------------------------------------------------------------------
 "DELETE FROM {0}FIRED_TRIGGERS WHERE SCHED_NAME = {1}"
 ----------------------------------------------------------------------------

2.2 获取ThreadExecutor 线程管理 misfireHandler.initialize();

public void initialize() {
		ThreadExecutor executor = getThreadExecutor();
		//getThreadExecutor ==  private ThreadExecutor threadExecutor = new DefaultThreadExecutor();
		executor.execute(MisfireHandler.this); //启动线程执行 对应job的 execute方法
		//MisfireHandler  ==  class MisfireHandler extends Thread  继承了Thread
}

3.1 唤醒所有等待的线程 schedThread.togglePause(false);

 schedThread.togglePause(false);
	//指示主处理循环在下一个可能的点暂停。
    void togglePause(boolean pause) {
        synchronized (sigLock) {
            paused = pause;

            if (paused) {
                signalSchedulingChange(0);
				------------------------------------------
				//发信号通知主要处理循环，已经进行了调度的改变 - 以便中断在等待misfire时间到达时可能发生的任何睡眠。
				public void signalSchedulingChange(long candidateNewNextFireTime) {
					synchronized(sigLock) {
						signaled = true;
						signaledNextFireTime = candidateNewNextFireTime;
						sigLock.notifyAll();  // private final Object sigLock = new Object();
					}
				}
				------------------------------------------
            } else {
                sigLock.notifyAll();//唤醒所有等待的线程
            }
        }
    }

附1：true 是如何转换为 1 的：

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