Quartz 之 Job Misfires

拼搏现实的明天。 2023-02-11 04:46 42阅读 0赞

项目地址：

[https://github.com/yuleiqq/quartz\_example/tree/master/quartz\_study][https_github.com_yuleiqq_quartz_example_tree_master_quartz_study]

此示例旨在演示与触发错误触发相关的概念。

程序将执行以下操作:

*  启动Quartz 调度器
 *  计划两个作业，每个作业将无限期地每三秒钟执行一次
 *  运行作业需要10秒(防止执行触发器每三秒触发一次)
 *  每个作业都有不同的失败指令
 *  程序将等待10分钟，以便两个作业有足够的时间运行
 *  停止调度器

代码有如下类组成:

<table style="width:500px;"> 
 <tbody> 
  <tr> 
   <td><strong>类名</strong></td> 
   <td><strong>描述</strong></td> 
  </tr> 
  <tr> 
   <td>MisfireExample</td> 
   <td>主程序</td> 
  </tr> 
  <tr> 
   <td>StatefulDumbJob</td> 
   <td>运行一个简单的job类，它的execute方法需要10秒钟</td> 
  </tr> 
 </tbody> 
</table>

### StatefulDumbJob ###

StatefulDumbJob是一个简单的作业，它打印它的执行时间，然后在完成之前等待一段时间。

等待时间量由作业参数EXECUTION\_DELAY定义。如果没有传入此作业参数，则该作业将默认为5秒的等待时间。该作业还保留自己的计数，即使用其JobDataMap中名为num\_的值执行了多少次。因为该类具有PersistJobDataAfterExecution注释，所以在每次执行之间保留执行计数。

package com.example06;
    
    import org.quartz.Job;
    import org.quartz.JobDataMap;
    import org.quartz.JobExecutionContext;
    import org.quartz.JobExecutionException;
    
    import java.util.Date;
    
    /**
     * @author :  yulei
     * @data :  2020/5/21 21:18
     * @Version :  1.0
     **/
    
    public class StatefulDumbJob  implements Job {
    
        //执行次数累计
        public static final String NUM_EXECUTIONS = "NumExecutions";
        //延迟执行时间
        public static final String EXECUTION_DELAY = "ExecutionDelay";
    
        public StatefulDumbJob() {
        }
    
        public void execute(JobExecutionContext context) throws JobExecutionException {
            System.err.println("---" + context.getJobDetail().getKey()
                    + " executing.[" + new Date() + "]");
            JobDataMap map = context.getJobDetail().getJobDataMap();
    
            int executeCount = 0;
            if (map.containsKey(NUM_EXECUTIONS)) {
                executeCount = map.getInt(NUM_EXECUTIONS);
            }
            executeCount++;
            map.put(NUM_EXECUTIONS, executeCount);
    
    
            long delay = 5000l;
            if (map.containsKey(EXECUTION_DELAY)) {
                delay = map.getLong(EXECUTION_DELAY);
            }
            try {
                Thread.sleep(delay);
            } catch (Exception ignore) {
            }
    
            System.err.println("  -" + context.getJobDetail().getKey()
                    + " complete (" + executeCount + ").");
    
    
        }
    }

### MisfireExample ###

程序首先获取调度程序的一个实例。这是通过创建一个StdSchedulerFactory来完成的，然后使用它来创建一个调度器。这将创建一个简单的基于RAM的调度器，因为没有特定的 quartz.properties配置文件 告诉它执行其他操作。

package com.example06;
    
    import static org.quartz.DateBuilder.nextGivenSecondDate;
    import static org.quartz.JobBuilder.newJob;
    import static org.quartz.SimpleScheduleBuilder.simpleSchedule;
    import static org.quartz.TriggerBuilder.newTrigger;
    
    import org.quartz.*;
    import org.quartz.impl.StdSchedulerFactory;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    
    import java.util.Date;
    
    /**
     * @author :  yulei
     * @data :  2020/5/21 21:30
     * @Version :  1.0
     **/
    
    public class MisfireExample {
    
        public void run() throws Exception {
            Logger log = LoggerFactory.getLogger(MisfireExample.class);
            log.info("------- Initializing -------------------");
            SchedulerFactory sf = new StdSchedulerFactory();
            Scheduler sched = sf.getScheduler();
            log.info("------- Initialization Complete -----------");
    
            Date startTime = nextGivenSecondDate(null, 15);
    
            //statefulJob1 3秒钟执行一次 (但是会延迟10秒)
            JobDetail job = newJob(StatefulDumbJob.class).withIdentity("statefulJob1", "group1")
                    .usingJobData(StatefulDumbJob.EXECUTION_DELAY, 10000L).build();
    
            SimpleTrigger trigger = newTrigger().withIdentity("trigger1", "group1").startAt(startTime)
                    .withSchedule(simpleSchedule().withIntervalInSeconds(3).repeatForever()).build();
    
            Date ft = sched.scheduleJob(job, trigger);
            log.info(job.getKey() + " will run at: " + ft + " and repeat: " + trigger.getRepeatCount() + " times, every "
                    + trigger.getRepeatInterval() / 1000 + " seconds");
    
    
            // statefulJob2每三秒钟运行一次
            //(但是它会延迟10秒—因此在几次迭代之后故意失火)
            job = newJob(StatefulDumbJob.class).withIdentity("statefulJob2", "group1")
                    .usingJobData(StatefulDumbJob.EXECUTION_DELAY, 10000L).build();
    
            trigger = newTrigger()
                    .withIdentity("trigger2", "group1")
                    .startAt(startTime)
                    .withSchedule(simpleSchedule().withIntervalInSeconds(3).repeatForever()
                            .withMisfireHandlingInstructionNowWithExistingCount()) // set misfire instructions
                    .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 ----------------");
            sched.start();
            log.info("------- Started Complete -----------------");
            try {
                // sleep for ten minutes for triggers to file....
                Thread.sleep(600L * 1000L);
            } catch (Exception e) {
                //
            }
            log.info("------- Shutting Down ---------------------");
    
            sched.shutdown(true);
    
            log.info("------- Shutdown Complete -----------------");
    
            SchedulerMetaData metaData = sched.getMetaData();
            log.info("Executed " + metaData.getNumberOfJobsExecuted() + " jobs.");
    
        }
    
        public static void main(String[] args) throws Exception {
            MisfireExample example = new MisfireExample();
            example.run();
    
        }
    
    }

withMisfireHandlingInstructionNowWithExistingCount  
——以当前时间为触发频率立即触发执行  
——执行至FinalTIme的剩余周期次数  
——以调度或恢复调度的时刻为基准的周期频率，FinalTime根据剩余次数和当前时间计算得到  
——调整后的FinalTime会略大于根据starttime计算的到的FinalTime值

执行后，运行结果如下：

--group1.statefulJob1 executing.[Thu May 21 22:07:15 CST 2020]
    ---group1.statefulJob2 executing.[Thu May 21 22:07:15 CST 2020]
      -group1.statefulJob1 complete (1).
      -group1.statefulJob2 complete (1).
    ---group1.statefulJob2 executing.[Thu May 21 22:07:25 CST 2020]
    ---group1.statefulJob1 executing.[Thu May 21 22:07:27 CST 2020]
      -group1.statefulJob2 complete (2).
    ---group1.statefulJob2 executing.[Thu May 21 22:07:35 CST 2020]
      -group1.statefulJob1 complete (2).
    ---group1.statefulJob1 executing.[Thu May 21 22:07:39 CST 2020]
      -group1.statefulJob2 complete (3).
    ---group1.statefulJob2 executing.[Thu May 21 22:07:45 CST 2020]
      -group1.statefulJob1 complete (3).
    ---group1.statefulJob1 executing.[Thu May 21 22:07:51 CST 2020]
      -group1.statefulJob2 complete (4).
    ---group1.statefulJob2 executing.[Thu May 21 22:07:55 CST 2020]
      -group1.statefulJob1 complete (4).
    ---group1.statefulJob1 executing.[Thu May 21 22:08:03 CST 2020]
      -group1.statefulJob2 complete (5).
    ---group1.statefulJob2 executing.[Thu May 21 22:08:05 CST 2020]

**可以看到 job2 在延迟10秒之后是立即执行的.   而 job1 还是按照 正常的3秒一次执行，错过上次频率，会在下次触发频率开始执行.**

[https_github.com_yuleiqq_quartz_example_tree_master_quartz_study]: https://github.com/yuleiqq/quartz_example/tree/master/quartz_study