文章目錄

• 概述
• 小例子
• • 創(chuàng)建一個在某個時間點執(zhí)行的 Trigger：
  • 創(chuàng)建一個在某個時間點執(zhí)行的 Trigger，并且隨后每 10 秒執(zhí)行一次，執(zhí)行 10 次
  • 創(chuàng)建一個 Trigger，并且在 5 分鐘后執(zhí)行一次
  • 創(chuàng)建一個 Trigger，并且立即執(zhí)行一次，以后每 5 分鐘執(zhí)行一次，直到 22:00
  • 創(chuàng)建一個 Trigger，并且在下一小時開始的時候執(zhí)行一次，以后每兩小時執(zhí)行一次，永久循環(huán)
• SimpleTrigger 的錯過觸發(fā)機制
• 示例
• 示例源碼

概述

SimpleTrigger 可以讓你在某個精確的時間執(zhí)行一次 Job，或者在某個精確的時間執(zhí)行之后在特定的時間間隔內(nèi)重復執(zhí)行。

例如，如果你想在 2015 年 1 月 13 日上午 11:23:54 時間點精確執(zhí)行，或者在這個時間點執(zhí)行完成后再執(zhí)行 5 次，每次間隔 10 秒鐘。

從SimpleTrigger接口的實現(xiàn)類SimpleTriggerImpl的源碼中我們可以看到如下屬性：

開始時間、結(jié)束時間、重復次數(shù)、重復間隔時間等，這些屬性看起來都很直觀，其中只有結(jié)束時間需要花點時間來特殊說明一下。

• 重復次數(shù)可以是 0，正整數(shù)（int），或者是SimpleTrigger.REPEAT_INDEFINITELY 常量值。

• 重復間隔時間必須是 0 或者正長整數(shù)（long），并且單位是毫秒。注意，如果將重復間隔時間設置為0，可能會發(fā)生 Trigger 同時觸發(fā)（并發(fā)）的問題。

如果熟悉Quartz 的DateBuilder類 ,你可能會發(fā)現(xiàn)使用它基于開始時間（或結(jié)束時間）來計算觸發(fā)次數(shù)非常有用。結(jié)束時間屬性將覆蓋重復次數(shù)屬性。

這在某些情況下非常有用，例如當你在創(chuàng)建好一個 Trigger 后，設置在指定的時間內(nèi)每 10 秒執(zhí)行一次，如果設置了結(jié)束時間就不用去計算開始時間到結(jié)束時間之間到底需要執(zhí)行多少次，你可以簡單的設置結(jié)束時間，并使用 REPEAT_INDEFINITELY 作為重復次數(shù)（你還可以簡單地寫一個足夠大的數(shù)字作為重復次數(shù)，只要這個數(shù)字大于在結(jié)束時間之前的實際執(zhí)行次數(shù)即可）。

SimpleTrigger 實例可以使用 TriggerBuilder（基于 Trigger 的主要屬性） 或 SimpleScheduleBuilder (基于 SimpleTrigger 的特殊屬性) 創(chuàng)建。要使用 DSL 風格需要先進行靜態(tài)導入：

import static org.quartz.TriggerBuilder.*; import static org.quartz.SimpleScheduleBuilder.*; import static org.quartz.DateBuilder.*:

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小例子

我們來看幾個小例子：

創(chuàng)建一個在某個時間點執(zhí)行的 Trigger：

SimpleTrigger trigger = (SimpleTrigger) newTrigger() .withIdentity("trigger1", "group1").startAt(myStartTime) // some Date .forJob("job1", "group1") // identify job with name, group strings.build();

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創(chuàng)建一個在某個時間點執(zhí)行的 Trigger，并且隨后每 10 秒執(zhí)行一次，執(zhí)行 10 次

trigger = newTrigger().withIdentity("trigger3", "group1").startAt(myTimeToStartFiring) // if a start time is not given (if this line were omitted), "now" is implied.withSchedule(simpleSchedule().withIntervalInSeconds(10).withRepeatCount(10)) // note that 10 repeats will give a total of 11 firings.forJob(myJob) // identify job with handle to its JobDetail itself .build();

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創(chuàng)建一個 Trigger，并且在 5 分鐘后執(zhí)行一次

trigger = (SimpleTrigger) newTrigger() .withIdentity("trigger5", "group1").startAt(futureDate(5, IntervalUnit.MINUTE)) // use DateBuilder to create a date in the future.forJob(myJobKey) // identify job with its JobKey.build();

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創(chuàng)建一個 Trigger，并且立即執(zhí)行一次，以后每 5 分鐘執(zhí)行一次，直到 22:00

trigger = newTrigger().withIdentity("trigger7", "group1").withSchedule(simpleSchedule().withIntervalInMinutes(5).repeatForever()).endAt(dateOf(22, 0, 0)).build();

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創(chuàng)建一個 Trigger，并且在下一小時開始的時候執(zhí)行一次，以后每兩小時執(zhí)行一次，永久循環(huán)

trigger = newTrigger().withIdentity("trigger8") // because group is not specified, "trigger8" will be in the default group.startAt(evenHourDate(null)) // get the next even-hour (minutes and seconds zero ("00:00")).withSchedule(simpleSchedule().withIntervalInHours(2).repeatForever())// note that in this example, 'forJob(..)' is not called // - which is valid if the trigger is passed to the scheduler along with the job .build();scheduler.scheduleJob(trigger, job);

花點時間研究所有 TriggerBuilder 和 SimpleScheduleBuilder 中的方法，你將更加熟悉如何使用，這些方法有很多都沒有在上面的例子中出現(xiàn)。

注意，TriggerBuilder（或者 Quartz 的其它 Builder）在你沒有顯式的設置屬性的時候會設置一個合理的默認屬性。例如，如果你沒有調(diào)用 withIdentity(…) 方法，那么 TriggerBuilder 將會為你的 Trigger 設置一個默認名稱；如果沒有調(diào)用 startAt(…) 方法，那么當前時間將會作為開始時間。

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SimpleTrigger 的錯過觸發(fā)機制

當 Quartz 發(fā)生錯過觸發(fā)事件后，SimpleTrigger 提供了幾個機制,這些機制以常量形式保存在 SimpleTrigger 中.

MISFIRE_INSTRUCTION_IGNORE_MISFIRE_POLICY MISFIRE_INSTRUCTION_FIRE_NOW MISFIRE_INSTRUCTION_RESCHEDULE_NOW_WITH_EXISTING_REPEAT_COUNT MISFIRE_INSTRUCTION_RESCHEDULE_NOW_WITH_REMAINING_REPEAT_COUNT MISFIRE_INSTRUCTION_RESCHEDULE_NEXT_WITH_REMAINING_COUNT MISFIRE_INSTRUCTION_RESCHEDULE_NEXT_WITH_EXISTING_COUNT

其中 Trigger.MISFIRE_INSTRUCTION_SMART_POLICY （智能策略）是所有 Trigger 的默認值。

當創(chuàng)建 SimpleTrigger 的時候，可以通過 SimpleSchedulerBuilder 指定錯過觸發(fā)機制：

trigger = newTrigger().withIdentity("trigger7", "group1").withSchedule(simpleSchedule().withIntervalInMinutes(5).repeatForever().withMisfireHandlingInstructionNextWithExistingCount()).build();

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示例

package com.xgj.quartz.quartzItself.simpleTriggerDemo;import java.util.Date;import org.apache.log4j.Logger; import org.quartz.Job; import org.quartz.JobExecutionContext; import org.quartz.JobExecutionException; import org.quartz.JobKey;public class SimpleJob implements Job {private static Logger _log = Logger.getLogger(SimpleJob.class);/*** Empty constructor for job initialization*/public SimpleJob() {}/*** <p>* Called by the <code>{@link org.quartz.Scheduler}</code> when a* <code>{@link org.quartz.Trigger}</code> fires that is associated with the* <code>Job</code>.* </p>* * @throws JobExecutionException* if there is an exception while executing the job.*/public void execute(JobExecutionContext context)throws JobExecutionException {// This job simply prints out its job name and the// date and time that it is runningJobKey jobKey = context.getJobDetail().getKey();_log.info("SimpleJob says: " + jobKey + " executing at " + new Date());} } package com.xgj.quartz.quartzItself.simpleTriggerDemo;import static org.quartz.DateBuilder.futureDate; import static org.quartz.JobBuilder.newJob; import static org.quartz.JobKey.jobKey; import static org.quartz.SimpleScheduleBuilder.simpleSchedule; import static org.quartz.TriggerBuilder.newTrigger;import java.util.Date;import org.apache.log4j.Logger; import org.quartz.DateBuilder; import org.quartz.DateBuilder.IntervalUnit; import org.quartz.JobDetail; import org.quartz.Scheduler; import org.quartz.SchedulerFactory; import org.quartz.SchedulerMetaData; import org.quartz.SimpleTrigger; import org.quartz.impl.StdSchedulerFactory;import com.xgj.quartz.quartzItself.quickDemo.SimpleJob;/*** * * @ClassName: SimpleTriggerExample* * @Description: This Example will demonstrate all of the basics of scheduling* capabilities of Quartz using Simple Triggers.* * @author: Mr.Yang* * @date: 2017年10月7日 下午8:49:43*/ public class SimpleTriggerExample {public void run() throws Exception {Logger log = Logger.getLogger(SimpleTriggerExample.class);log.info("------- Initializing -------------------");// First we must get a reference to a schedulerSchedulerFactory sf = new StdSchedulerFactory();Scheduler sched = sf.getScheduler();log.info("------- Initialization Complete --------");log.info("------- Scheduling Jobs ----------------");// jobs can be scheduled before sched.start() has been called// get a "nice round" time a few seconds in the future...Date startTime = DateBuilder.nextGivenSecondDate(null, 15);// job1 will only fire once at date/time "ts"JobDetail job = newJob(SimpleJob.class).withIdentity("job1", "group1").build();SimpleTrigger trigger = (SimpleTrigger) newTrigger().withIdentity("trigger1", "group1").startAt(startTime).build();// schedule it to run!Date ft = sched.scheduleJob(job, trigger);log.info(job.getKey() + " will run at: " + ft + " and repeat: "+ trigger.getRepeatCount() + " times, every "+ trigger.getRepeatInterval() / 1000 + " seconds");// job2 will only fire once at date/time "ts"job = newJob(SimpleJob.class).withIdentity("job2", "group1").build();trigger = (SimpleTrigger) newTrigger().withIdentity("trigger2", "group1").startAt(startTime).build();ft = sched.scheduleJob(job, trigger);log.info(job.getKey() + " will run at: " + ft + " and repeat: "+ trigger.getRepeatCount() + " times, every "+ trigger.getRepeatInterval() / 1000 + " seconds");// job3 will run 11 times (run once and repeat 10 more times)// job3 will repeat every 10 secondsjob = newJob(SimpleJob.class).withIdentity("job3", "group1").build();trigger = newTrigger().withIdentity("trigger3", "group1").startAt(startTime).withSchedule(simpleSchedule().withIntervalInSeconds(10).withRepeatCount(10)).build();ft = sched.scheduleJob(job, trigger);log.info(job.getKey() + " will run at: " + ft + " and repeat: "+ trigger.getRepeatCount() + " times, every "+ trigger.getRepeatInterval() / 1000 + " seconds");// the same job (job3) will be scheduled by a another trigger// this time will only repeat twice at a 70 second intervaltrigger = newTrigger().withIdentity("trigger3", "group2").startAt(startTime).withSchedule(simpleSchedule().withIntervalInSeconds(10).withRepeatCount(2)).forJob(job).build();ft = sched.scheduleJob(trigger);log.info(job.getKey() + " will [also] run at: " + ft + " and repeat: "+ trigger.getRepeatCount() + " times, every "+ trigger.getRepeatInterval() / 1000 + " seconds");// job4 will run 6 times (run once and repeat 5 more times)// job4 will repeat every 10 secondsjob = newJob(SimpleJob.class).withIdentity("job4", "group1").build();trigger = newTrigger().withIdentity("trigger4", "group1").startAt(startTime).withSchedule(simpleSchedule().withIntervalInSeconds(10).withRepeatCount(5)).build();ft = sched.scheduleJob(job, trigger);log.info(job.getKey() + " will run at: " + ft + " and repeat: "+ trigger.getRepeatCount() + " times, every "+ trigger.getRepeatInterval() / 1000 + " seconds");// job5 will run once, five minutes in the futurejob = newJob(SimpleJob.class).withIdentity("job5", "group1").build();trigger = (SimpleTrigger) newTrigger().withIdentity("trigger5", "group1").startAt(futureDate(5, IntervalUnit.MINUTE)).build();ft = sched.scheduleJob(job, trigger);log.info(job.getKey() + " will run at: " + ft + " and repeat: "+ trigger.getRepeatCount() + " times, every "+ trigger.getRepeatInterval() / 1000 + " seconds");// job6 will run indefinitely, every 40 secondsjob = newJob(SimpleJob.class).withIdentity("job6", "group1").build();trigger = newTrigger().withIdentity("trigger6", "group1").startAt(startTime).withSchedule(simpleSchedule().withIntervalInSeconds(40).repeatForever()).build();ft = sched.scheduleJob(job, trigger);log.info(job.getKey() + " will run at: " + ft + " and repeat: "+ trigger.getRepeatCount() + " times, every "+ trigger.getRepeatInterval() / 1000 + " seconds");log.info("------- Starting Scheduler ----------------");// All of the jobs have been added to the scheduler, but none of the// jobs// will run until the scheduler has been startedsched.start();log.info("------- Started Scheduler -----------------");// jobs can also be scheduled after start() has been called...// job7 will repeat 20 times, repeat every five minutesjob = newJob(SimpleJob.class).withIdentity("job7", "group1").build();trigger = newTrigger().withIdentity("trigger7", "group1").startAt(startTime).withSchedule(simpleSchedule().withIntervalInMinutes(5).withRepeatCount(20)).build();ft = sched.scheduleJob(job, trigger);log.info(job.getKey() + " will run at: " + ft + " and repeat: "+ trigger.getRepeatCount() + " times, every "+ trigger.getRepeatInterval() / 1000 + " seconds");// jobs can be fired directly... (rather than waiting for a trigger)job = newJob(SimpleJob.class).withIdentity("job8", "group1").storeDurably().build();sched.addJob(job, true);log.info("'Manually' triggering job8...");sched.triggerJob(jobKey("job8", "group1"));log.info("------- Waiting 30 seconds... --------------");try {// wait 33 seconds to show jobsThread.sleep(30L * 1000L);// executing...} catch (Exception e) {//}// jobs can be re-scheduled...// job 7 will run immediately and repeat 10 times for every secondlog.info("------- Rescheduling... --------------------");trigger = newTrigger().withIdentity("trigger7", "group1").startAt(startTime).withSchedule(simpleSchedule().withIntervalInMinutes(5).withRepeatCount(20)).build();ft = sched.rescheduleJob(trigger.getKey(), trigger);log.info("job7 rescheduled to run at: " + ft);log.info("------- Waiting five minutes... ------------");try {// wait five minutes to show jobsThread.sleep(300L * 1000L);// executing...} catch (Exception e) {//}log.info("------- Shutting Down ---------------------");sched.shutdown(true);log.info("------- Shutdown Complete -----------------");// display some stats about the schedule that just ranSchedulerMetaData metaData = sched.getMetaData();log.info("Executed " + metaData.getNumberOfJobsExecuted() + " jobs.");}public static void main(String[] args) throws Exception {SimpleTriggerExample example = new SimpleTriggerExample();example.run();} }

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示例源碼

代碼已托管到Github—> https://github.com/yangshangwei/SpringMaster

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