Quartz

来源:互联网 发布:美工设计工作流程 编辑:程序博客网 时间:2024/05/29 19:03
一、Quartz简介

Quartz是一个开放源码项目,专注于任务调度器,提供了极为广泛的特性如持久化任务,集群和分布式任务等。Spring对Quartz的集成与其对JDK Timer的集成在任务、触发器和调度计划的声明式配置方面等都非常相似。

Quartz的核心由两个接口和两个类组成:Job和Scheduler接口,JobDetail和Trigger类。不同于JDK Timer,任务不是从实现一个Job接口的类实例开始运行,实际上Quartz在需要的时候才创建job类实例。可以使用JobDetail类来包装任务状态,并传递一个信息给Job,或在一个Job的多次执行过程之间保存信息。

二、Quartz任务调度

1. 简单任务调度

在Quartz中创建一个任务并执行,只需要实现Job接口类,在其execute()方法中处理你的业务逻辑。下面举例说明。

HelloWorldJob.java
Java代码 复制代码 收藏代码
  1. package com.learnworld.quartz;
  2. import org.quartz.Job;
  3. import org.quartz.JobExecutionContext;
  4. import org.quartz.JobExecutionException;
  5. public class HelloWorldJobimplements Job {
  6. public void execute(JobExecutionContext context)throws JobExecutionException {
  7. //实现你的业务逻辑
  8. System.out.println("Hello!");
  9. }
  10. }
package com.learnworld.quartz;import org.quartz.Job;import org.quartz.JobExecutionContext;import org.quartz.JobExecutionException;public class HelloWorldJob implements Job {public void execute(JobExecutionContext context) throws JobExecutionException {                  //实现你的业务逻辑System.out.println("Hello!");}}


HelloScheduling.java
Java代码 复制代码 收藏代码
  1. package com.learnworld.quartz;
  2. import java.util.Date;
  3. import org.quartz.JobDetail;
  4. import org.quartz.Scheduler;
  5. import org.quartz.SimpleTrigger;
  6. import org.quartz.Trigger;
  7. import org.quartz.impl.StdSchedulerFactory;
  8. public class HelloScheduling {
  9. public staticvoid main(String[] args) throws Exception {
  10. Scheduler scheduler = new StdSchedulerFactory().getScheduler();
  11. scheduler.start();
  12. JobDetail jobDetail = new JobDetail("helloWorldJob",
  13. Scheduler.DEFAULT_GROUP, HelloWorldJob.class);
  14. Trigger trigger = new SimpleTrigger("simpleTrigger",
  15. Scheduler.DEFAULT_GROUP, new Date(),null,
  16. SimpleTrigger.REPEAT_INDEFINITELY, 1000);
  17. scheduler.scheduleJob(jobDetail, trigger);
  18. }
  19. }
package com.learnworld.quartz;import java.util.Date;import org.quartz.JobDetail;import org.quartz.Scheduler;import org.quartz.SimpleTrigger;import org.quartz.Trigger;import org.quartz.impl.StdSchedulerFactory;public class HelloScheduling {public static void main(String[] args) throws Exception {Scheduler scheduler = new StdSchedulerFactory().getScheduler();scheduler.start();JobDetail jobDetail = new JobDetail("helloWorldJob",Scheduler.DEFAULT_GROUP, HelloWorldJob.class);Trigger trigger = new SimpleTrigger("simpleTrigger",Scheduler.DEFAULT_GROUP, new Date(), null,SimpleTrigger.REPEAT_INDEFINITELY, 1000);scheduler.scheduleJob(jobDetail, trigger);}}


需要说明几点:

1)开始使用StdSchedulerFactory来获取Scheduler的实例。每一个scheduler可以被启动(start)、中止(stop)和暂停(pause)。如果一个scheduler没有被启动或已经被暂停,则没有触发器会被启用,所以首先使用start()方法启动scheduler。

2)创建JobDetail实例。它的构造参数有三个,第一个是任务名,任务名可以被用作参数来应用需要暂停的任务;第二个是组名,组名可以用来引用一组被集合在一起的任务,这里采用缺省组名,每一个任务名在组内必须是唯一的;第三个参数是实现了特定任务的类。

3)创建Trigger实例。我们使用SimpleTrigger类,它提供了类似JDK Timer风格的触发器行为。它的构造参数有六个,第一个和第二个为触发器名和组名,和上面类似;第三个为任务开始时间;第四个为结束时间,如果设置为空,表示不存在结束时间;第五个为重复次数,允许你指的触发器被触发的最大次数,使用REPEAT_INDEFINITELY允许触发器可以被触发无限次;第六个是触发器运行的时间间隔,是毫秒数。

4)最后通过scheduler.scheduleJob()方法调度任务。

2. 使用JobDetail传递数据

每个JobDetail实例都有关联的JobDataMap实例,它实现了Map接口并允许通过键值来传递任务相关的数据。任务也可以修改JobDataMap中的数据,在同一任务的多次执行之间传递数据。下面举例说明。

MessageJob.java
Java代码 复制代码 收藏代码
  1. package com.learnworld.quartz;
  2. import java.util.Map;
  3. import org.quartz.Job;
  4. import org.quartz.JobExecutionContext;
  5. import org.quartz.JobExecutionException;
  6. public class MessageJobimplements Job {
  7. public void execute(JobExecutionContext context)throws JobExecutionException {
  8. Map properties = context.getJobDetail().getJobDataMap();
  9. System.out.println("Previous Fire Time: " + context.getPreviousFireTime());
  10. System.out.println("Current Fire Time: " + context.getFireTime());
  11. System.out.println("Next Fire Time: " + context.getNextFireTime());
  12. System.out.println(properties.get("message"));
  13. }
  14. }
package com.learnworld.quartz;import java.util.Map;import org.quartz.Job;import org.quartz.JobExecutionContext;import org.quartz.JobExecutionException;public class MessageJob implements Job {public void execute(JobExecutionContext context) throws JobExecutionException {Map properties = context.getJobDetail().getJobDataMap();System.out.println("Previous Fire Time: " + context.getPreviousFireTime());System.out.println("Current Fire Time: " + context.getFireTime());System.out.println("Next Fire Time: " + context.getNextFireTime());System.out.println(properties.get("message"));}}


MessageScheduling.java
Java代码 复制代码 收藏代码
  1. package com.learnworld.quartz;
  2. import java.util.Date;
  3. import java.util.Map;
  4. import org.quartz.JobDetail;
  5. import org.quartz.Scheduler;
  6. import org.quartz.SimpleTrigger;
  7. import org.quartz.Trigger;
  8. import org.quartz.impl.StdSchedulerFactory;
  9. public class MessageScheduling {
  10. public staticvoid main(String[] args) throws Exception {
  11. Scheduler scheduler = new StdSchedulerFactory().getScheduler();
  12. scheduler.start();
  13. JobDetail jobDetail = new JobDetail("messageJob",
  14. Scheduler.DEFAULT_GROUP, MessageJob.class);
  15. Map map = jobDetail.getJobDataMap();
  16. map.put("message", "This is a message from Quartz");
  17. Trigger trigger = new SimpleTrigger("simpleTrigger",
  18. Scheduler.DEFAULT_GROUP, new Date(),new Date("Sat, 12 Aug 2011 13:30:00 GMT+0430"),
  19. SimpleTrigger.REPEAT_INDEFINITELY, 5000);
  20. scheduler.scheduleJob(jobDetail, trigger);
  21. }
  22. }
package com.learnworld.quartz;import java.util.Date;import java.util.Map;import org.quartz.JobDetail;import org.quartz.Scheduler;import org.quartz.SimpleTrigger;import org.quartz.Trigger;import org.quartz.impl.StdSchedulerFactory;public class MessageScheduling {public static void main(String[] args) throws Exception {Scheduler scheduler = new StdSchedulerFactory().getScheduler();scheduler.start();JobDetail jobDetail = new JobDetail("messageJob",Scheduler.DEFAULT_GROUP, MessageJob.class);Map map = jobDetail.getJobDataMap();map.put("message", "This is a message from Quartz");Trigger trigger = new SimpleTrigger("simpleTrigger",Scheduler.DEFAULT_GROUP, new Date(), new Date("Sat, 12 Aug 2011 13:30:00 GMT+0430"),SimpleTrigger.REPEAT_INDEFINITELY, 5000);scheduler.scheduleJob(jobDetail, trigger);}}


3. 使用CronTrigger

上面提到了SimpleTrigger类,它提供了类似JDK Timer风格的触发器功能。Quartz的出色在于它使用CronTrigger提供了对复杂触发器的支持。

一个CronTrigger表达式,包含六个必须组件和一个可选组件。关于cron表达式,可以参考这篇文档:http://www.quartz-scheduler.org/docs/tutorials/crontrigger.html

下面举例说明CronTrigger的使用。

CronWithCalendarScheduling.java
Java代码 复制代码 收藏代码
  1. package com.learnworld.quartz;
  2. import java.util.Calendar;
  3. import java.util.Date;
  4. import java.util.Map;
  5. import org.quartz.CronTrigger;
  6. import org.quartz.JobDetail;
  7. import org.quartz.Scheduler;
  8. import org.quartz.SimpleTrigger;
  9. import org.quartz.Trigger;
  10. import org.quartz.impl.StdSchedulerFactory;
  11. import org.quartz.impl.calendar.HolidayCalendar;
  12. public class CronWithCalendarScheduling {
  13. public staticvoid main(String[] args) throws Exception {
  14. Calendar cal = Calendar.getInstance();
  15. cal.set(2010, Calendar.OCTOBER,31);
  16. HolidayCalendar calendar = new HolidayCalendar();
  17. calendar.addExcludedDate(cal.getTime());
  18. Scheduler scheduler = new StdSchedulerFactory().getScheduler();
  19. scheduler.start();
  20. scheduler.addCalendar("calendar", calendar,true, false);
  21. JobDetail jobDetail = new JobDetail("messageJob",
  22. Scheduler.DEFAULT_GROUP, MessageJob.class);
  23. Map map = jobDetail.getJobDataMap();
  24. map.put("message", "This is a message from Quartz");
  25. String cronExpression = "3/5 * 17,18,19,20 * * ?";
  26. Trigger trigger = new CronTrigger("cronTrigger",
  27. Scheduler.DEFAULT_GROUP, cronExpression);
  28. scheduler.scheduleJob(jobDetail, trigger);
  29. }
  30. }
package com.learnworld.quartz;import java.util.Calendar;import java.util.Date;import java.util.Map;import org.quartz.CronTrigger;import org.quartz.JobDetail;import org.quartz.Scheduler;import org.quartz.SimpleTrigger;import org.quartz.Trigger;import org.quartz.impl.StdSchedulerFactory;import org.quartz.impl.calendar.HolidayCalendar;public class CronWithCalendarScheduling {public static void main(String[] args) throws Exception {Calendar cal = Calendar.getInstance();cal.set(2010, Calendar.OCTOBER, 31);HolidayCalendar calendar  = new HolidayCalendar();calendar.addExcludedDate(cal.getTime());Scheduler scheduler = new StdSchedulerFactory().getScheduler();scheduler.start();scheduler.addCalendar("calendar", calendar, true, false);JobDetail jobDetail = new JobDetail("messageJob",Scheduler.DEFAULT_GROUP, MessageJob.class);Map map = jobDetail.getJobDataMap();map.put("message", "This is a message from Quartz");String cronExpression = "3/5 * 17,18,19,20 * * ?";Trigger trigger = new CronTrigger("cronTrigger",Scheduler.DEFAULT_GROUP, cronExpression);scheduler.scheduleJob(jobDetail, trigger);}}


需要说明几点:

1)创建了HolidayCalendar实例,使用addExcluderData()方法排除了2010年10月31日。再使用addCalendar()方法,将这个Calendar加入到Scheduler中。

2)这个cron表达式的含义是,每天17:00-20:59之间每一分钟的第三秒开始运行,每五秒执行一次。

三. Spring对Quartz调度的支持

Spring对Quartz集成与其对JDK Timer调度集成类似,你可以在配置文件中配置任务调度。仅需要在程序里加载ApplicationContext,Spring会自动启动调度器。

quartz.xml
Java代码 复制代码 收藏代码
  1. <?xml version="1.0" encoding="UTF-8"?>
  2. <!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN""http://www.springframework.org/dtd/spring-beans.dtd">
  3. <beans>
  4. <bean id="job"
  5. class="org.springframework.scheduling.quartz.JobDetailBean">
  6. <property name="jobClass">
  7. <value> com.learnworld.quartz.MessageJob </value>
  8. </property>
  9. <property name="jobDataAsMap">
  10. <map>
  11. <entry key="message">
  12. <value>This is a message from Spring Quartz configuration!</value>
  13. </entry>
  14. </map>
  15. </property>
  16. </bean>
  17. <bean id="trigger" class="org.springframework.scheduling.quartz.SimpleTriggerBean">
  18. <property name="startDelay">
  19. <value>1000</value>
  20. </property>
  21. <property name="repeatInterval">
  22. <value>3000</value>
  23. </property>
  24. <property name="jobDetail">
  25. <ref local="job" />
  26. </property>
  27. </bean>
  28. <bean id="schdulerFactory" class="org.springframework.scheduling.quartz.SchedulerFactoryBean">
  29. <property name="triggers">
  30. <list>
  31. <ref local="trigger" />
  32. </list>
  33. </property>
  34. </bean>
  35. </beans>
<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd"><beans><bean id="job"class="org.springframework.scheduling.quartz.JobDetailBean"><property name="jobClass"><value> com.learnworld.quartz.MessageJob </value></property><property name="jobDataAsMap"><map><entry key="message"><value>This is a message from Spring Quartz configuration!</value></entry></map></property></bean><bean id="trigger" class="org.springframework.scheduling.quartz.SimpleTriggerBean"><property name="startDelay"><value>1000</value></property><property name="repeatInterval"><value>3000</value></property><property name="jobDetail"><ref local="job" /></property></bean><bean id="schdulerFactory" class="org.springframework.scheduling.quartz.SchedulerFactoryBean"><property name="triggers"><list><ref local="trigger" /></list></property></bean></beans>


SimpleSpringQuartzIntegration.java
Java代码 复制代码 收藏代码
  1. package com.learnworld.quartz;
  2. import org.springframework.context.ApplicationContext;
  3. import org.springframework.context.support.FileSystemXmlApplicationContext;
  4. public class SimpleSpringQuartzIntegration {
  5. public staticvoid main(String[] args) {
  6. ApplicationContext ac = new FileSystemXmlApplicationContext("src/conf/quartz.xml");
  7. }
  8. }
package com.learnworld.quartz;import org.springframework.context.ApplicationContext;import org.springframework.context.support.FileSystemXmlApplicationContext;public class SimpleSpringQuartzIntegration {public static void main(String[] args) {ApplicationContext ac = new FileSystemXmlApplicationContext("src/conf/quartz.xml");}}


需要说明几点:

1)采用JobDetailBean类,它扩展了JobDetai类,采用可声明方式配置任务数据。缺省情况下,采用<bean>标签的id作为任务名,使用缺省组作为组名,通过jobDataAsMap作为配置任务数据。

2)建立触发器。可以选择SimpleTriggerBean或CronTriggerBean类。SimpleTriggerBean缺省情况下把可重复执行次数设为无限。

3)创建schedulerFactory。缺省情况下,SchedulerFactoryBean创建一个StdSchedulerFactory的实例,后者创建Scheduler的实现。可以通过设置schedulerFactoryClass属性来覆盖这个行为,需要继承SchedulerFactory接口来实现你自己的版本。