查看源码注释可以得知：
JobExecutionContext 是一个包含了各种上下文信息的句柄，指向执行中的JobDetail 实例 和 执行完成的Trigger实例.
JobExecutionContext中有一个简便的方法可以获取执行上下文中的JobDataMap , 它是JobDetail 中的JobDataMap 和 Trigger 中的JobDataMap 的合并，后者的JobDataMap 会覆盖前者相同名称的值.
注意： 不要期望通过这个返回的JobDataMap 的set 方法设置 某个值 持久化到作业自身的JobDataMap ，即使 有@PersistJobDataAfterExecution .
试图更改此映射的内容通常会导致IllegalStateException 异常.
public JobDataMap getMergedJobDataMap();
我们看下如下例子.
package com.example04;
import org.quartz.*;
import org.quartz.impl.StdSchedulerFactory;
/**
* 1442554244
* JobExecutionContext例子
**/
public class CronTriggerExample {
public void run () throws SchedulerException {
//实例化调度器
Scheduler scheduler =StdSchedulerFactory.getDefaultScheduler();
//实例化job
JobDetail job1 = JobBuilder.newJob(SimpleJob.class)
.withIdentity("job1","group1")
//设置jobDetail值
.usingJobData("name","tom")
.usingJobData("email","123@qq.com")
// 当job 没有绑定trigger时，继续保存在调度器中
.storeDurably()
.build();
//若有相同名称的job ，是否替换，否则抛出异常, 使用这个方法，必须保证 isDurable=true
scheduler.addJob(job1,false);
//定义Contrigger
CronTrigger cronTrigger1 = TriggerBuilder.newTrigger()
.withIdentity("trigger1","group1")
//设置JobDatail值
.usingJobData("email","456@qq.com")
.withSchedule(CronScheduleBuilder.cronSchedule(" 0/5 * * * * ? "))
.forJob(job1)
.build();
scheduler.scheduleJob(cronTrigger1);
scheduler.start();
}
public static void main(String[] args) throws SchedulerException {
CronTriggerExample example = new CronTriggerExample();
example.run();
}
}
package com.example04;
import org.quartz.*;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.Date;
/**
* @author yulei
*/
public class SimpleJob implements Job {
private static Logger log = LoggerFactory.getLogger(SimpleJob.class);
public SimpleJob() {
}
public void execute(JobExecutionContext context) throws JobExecutionException {
JobKey jobKey = context.getJobDetail().getKey();
JobDataMap jobDataMap = context.getMergedJobDataMap();
log.info("name: "+jobDataMap.getString("name")+", email: "+jobDataMap.getString("email"));
log.info("SimpleJob says: " + jobKey + " executing at " + new Date());
}
}
打印内容如下：
INFO] 27 一月 11:52:32.084 上午 main [org.quartz.impl.StdSchedulerFactory]
Using default implementation for ThreadExecutor
[INFO] 27 一月 11:52:32.109 上午 main [org.quartz.core.SchedulerSignalerImpl]
Initialized Scheduler Signaller of type: class org.quartz.core.SchedulerSignalerImpl
[INFO] 27 一月 11:52:32.109 上午 main [org.quartz.core.QuartzScheduler]
Quartz Scheduler v.2.3.0 created.
[INFO] 27 一月 11:52:32.110 上午 main [org.quartz.simpl.RAMJobStore]
RAMJobStore initialized.
[INFO] 27 一月 11:52:32.111 上午 main [org.quartz.core.QuartzScheduler]
Scheduler meta-data: Quartz Scheduler (v2.3.0) 'MyScheduler' with instanceId 'NON_CLUSTERED'
Scheduler class: 'org.quartz.core.QuartzScheduler' - running locally.
NOT STARTED.
Currently in standby mode.
Number of jobs executed: 0
Using thread pool 'org.quartz.simpl.SimpleThreadPool' - with 20 threads.
Using job-store 'org.quartz.simpl.RAMJobStore' - which does not support persistence. and is not clustered.
[INFO] 27 一月 11:52:32.112 上午 main [org.quartz.impl.StdSchedulerFactory]
Quartz scheduler 'MyScheduler' initialized from default resource file in Quartz package: 'quartz.properties'
[INFO] 27 一月 11:52:32.112 上午 main [org.quartz.impl.StdSchedulerFactory]
Quartz scheduler version: 2.3.0
[INFO] 27 一月 11:52:32.135 上午 main [org.quartz.core.QuartzScheduler]
Scheduler MyScheduler_$_NON_CLUSTERED started.
[INFO] 27 一月 11:52:35.007 上午 MyScheduler_Worker-1 [com.example04.SimpleJob]
name: tom, email: 456@qq.com
[INFO] 27 一月 11:52:35.011 上午 MyScheduler_Worker-1 [com.example04.SimpleJob]
SimpleJob says: group1.job1 executing at Mon Jan 27 11:52:35 CST 2020
由次可以看出，触发器中的JobDataMap 会覆盖JobDetail 中相同名称的key 的value 。