浅谈JobExecutionContext & JobDataMap

JobExecutionContext是什么？

• 当Scheduler调用一个Job，就会将JobExecutionContext传递给Job的 execute() 方法；
• Job能通过JobExecutionContext对象访问到Quartz运行时候的环境以及Job本身的明细数据。

JobDataMap是什么？

• 在进行任务调度时JobDataMap存储在JobExecutionContext中，非常方便获取
• JobDataMap可以用来装载任何可以序列化的数据对象，当Job实例对象被执行时，这些参数对象会传递给它。
• JobDataMap实现了JDK的Map 接口，并且添加了一些非常方便的方法用来存储基本数据类型。

JobDataMap的获取方式

• 方式一：从Map里面直接获取

import java.text.NumberFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

import org.quartz.Job;
import org.quartz.JobDataMap;
import org.quartz.JobExecutionContext;
import org.quartz.JobExecutionException;
import org.quartz.JobKey;
import org.quartz.TriggerKey;

public class HelloJob implements Job{

    public void execute(JobExecutionContext context) throws JobExecutionException {

        //打印当前的执行时间
        Date date = new Date();
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String currentTime = sdf.format(date);
        System.out.println("Current Exec Time : "+currentTime);
        //编写具体的业务逻辑

        JobKey key = context.getJobDetail().getKey();
        System.out.println("my name is :"+key.getName()+" and group is:" +key.getGroup());
        TriggerKey trkey = context.getTrigger().getKey();
        System.out.println("my name is: "+trkey.getName()+" and group is:"+trkey.getGroup());
        JobDataMap dataMap = context.getJobDetail().getJobDataMap();
        JobDataMap tdataMap = context.getTrigger().getJobDataMap();
        String jobMessage = dataMap.getString("message");
        Float FloatJobValue = dataMap.getFloat("FloatJobValue");
        String triggerMessage = tdataMap.getString("message");
        Double DoubleTriggerValue = tdataMap.getDouble("DoubleTriggerValue");

        System.out.println(jobMessage);
        System.out.println(FloatJobValue);
        System.out.println(triggerMessage);
        System.out.println(DoubleTriggerValue);
    }

}

import org.quartz.JobBuilder;
import org.quartz.JobDetail;
import org.quartz.Scheduler;
import org.quartz.SchedulerException;
import org.quartz.SchedulerFactory;
import org.quartz.SimpleScheduleBuilder;
import org.quartz.Trigger;
import org.quartz.TriggerBuilder;
import org.quartz.impl.StdSchedulerFactory;

public class HelloScheduler {
    public static void main(String[] args) throws SchedulerException {
        //创建一个JobDetail实例，将该实例与HelloJob class绑定
        JobDetail jobDetail = JobBuilder.newJob(HelloJob.class)
                .withIdentity("myJob", "group1")
                .usingJobData("message", "hello myJob1")
                .usingJobData("FloatJobValue", 3.14f).build();
        //创建一个Trigger实例，定义该Job立即执行，并且每隔2秒钟重复执行一次，直到永远
        Trigger trigger = TriggerBuilder.newTrigger()
                .withIdentity("myTrigger", "group1")
                .usingJobData("message", "hello myTrigger1")
                .usingJobData("DoubleTriggerValue", 2.0D)
                .startNow().
                withSchedule(SimpleScheduleBuilder.simpleSchedule().withIntervalInSeconds(2).repeatForever())
                .build();
        //创建Scheduler实例
        SchedulerFactory sfact = new StdSchedulerFactory();
        Scheduler scheduler = sfact.getScheduler();
        scheduler.start();
        scheduler.scheduleJob(jobDetail, trigger);
    }

}

import java.text.NumberFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

import org.quartz.Job;
import org.quartz.JobDataMap;
import org.quartz.JobExecutionContext;
import org.quartz.JobExecutionException;
import org.quartz.JobKey;
import org.quartz.TriggerKey;

public class HelloJob implements Job{

    public void execute(JobExecutionContext context) throws JobExecutionException {

        //打印当前的执行时间
        Date date = new Date();
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String currentTime = sdf.format(date);
        System.out.println("Current Exec Time : "+currentTime);
        //编写具体的业务逻辑        

        JobKey key = context.getJobDetail().getKey();
        System.out.println("my name is :"+key.getName()+" and group is:" +key.getGroup());
        TriggerKey trkey = context.getTrigger().getKey();
        System.out.println("my name is: "+trkey.getName()+" and group is:"+trkey.getGroup());

        JobDataMap dataMap = context.getMergedJobDataMap();        

        String jobMessage = dataMap.getString("message");
        Float FloatJobValue = dataMap.getFloat("FloatJobValue");
        String triggerMessage = dataMap.getString("message");
        Double DoubleTriggerValue = dataMap.getDouble("DoubleTriggerValue");

        System.out.println(jobMessage);
        System.out.println(FloatJobValue);
        System.out.println(triggerMessage);
        System.out.println(DoubleTriggerValue);
    }

}

方式二：Job实现类中添加setter方法对应JobDataMap的键值（Quartz框架默认的JobFactory 实现类在初始化job实例对象时会自动地调用这些setter方法）

package com.test.quartz.myquartz;

import java.text.SimpleDateFormat;
import java.util.Date;
import org.quartz.Job;
import org.quartz.JobDataMap;
import org.quartz.JobExecutionContext;
import org.quartz.JobExecutionException;
import org.quartz.JobKey;
import org.quartz.TriggerKey;

public class HelloJob implements Job{

     private String message;
    private Float FloatJobValue;
    private Double DoubleTriggerValue;

  public void setMessage(String message) {
        this.message = message;
    }
 public void setFloatJobValue(Float floatJobValue) {
        FloatJobValue = floatJobValue;
    }
public void setDoubleTriggerValue(Double doubleTriggerValue) {
        DoubleTriggerValue = doubleTriggerValue;
    }

    public void execute(JobExecutionContext context) throws JobExecutionException {

        //打印当前的执行时间
        Date date = new Date();
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String currentTime = sdf.format(date);
        System.out.println("Current Exec Time : "+currentTime);
        //编写具体的业务逻辑        

        JobKey key = context.getJobDetail().getKey();
        System.out.println("my name is :"+key.getName()+" and group is:" +key.getGroup());
        TriggerKey trkey = context.getTrigger().getKey();
        System.out.println("my name is: "+trkey.getName()+" and group is:"+trkey.getGroup());

        System.out.println("message is :" +message);
        System.out.println("FloatJobValue is :" +FloatJobValue);
        System.out.println("DoubleTriggerValue is :" +DoubleTriggerValue);
    }

}