Spring Boot中实现定时任务应用实践

时间:2019-04-14
本文章向大家介绍Spring Boot中实现定时任务应用实践,主要包括Spring Boot中实现定时任务应用实践使用实例、应用技巧、基本知识点总结和需要注意事项,具有一定的参考价值,需要的朋友可以参考一下。

前言

在Spring Boot中实现定时任务功能,可以通过Spring自带的定时任务调度,也可以通过集成经典开源组件Quartz实现任务调度。

本文将详细介绍关于Spring Boot实现定时任务应用的相关内容,分享出来供大家参考学习,下面话不多说了,来一起看看详细的介绍吧。

一、Spring定时器

1、cron表达式方式

使用自带的定时任务,非常简单,只需要像下面这样,加上注解就好,不需要像普通定时任务框架那样继承任何定时处理接口 ,简单示例代码如下:

package com.power.demo.scheduledtask.simple;
import com.power.demo.util.DateTimeUtil;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;
import java.util.Date;
@Component
@EnableScheduling
public class SpringTaskA {
 /**
 * CRON表达式参考:http://cron.qqe2.com/
 **/
 @Scheduled(cron = "*/5 * * * * ?", zone = "GMT+8:00")
 private void timerCron() {

 try {
 Thread.sleep(100);
 } catch (Exception e) {
 e.printStackTrace();
 }

 System.out.println(String.format("(timerCron)%s 每隔5秒执行一次,记录日志", DateTimeUtil.fmtDate(new Date())));

 }

}

SpringTaskA

上述代码中,在一个类上添加@EnableScheduling注解,在方法上加上@Scheduled,配置下 cron 表达式,一个最最简单的cron定时任务就完成了。cron表达式的各个组成部分,可以参考下面:

@Scheduled(cron = "[Seconds] [Minutes] [Hours] [Day of month] [Month] [Day of week] [Year]")

2、fixedRate和fixedDelay

@Scheduled注解除了cron表达式,还有其他配置方式,比如fixedRate和fixedDelay,下面这个示例通过配置方式的不同,实现不同形式的定时任务调度,示例代码如下:

package com.power.demo.scheduledtask.simple;
import com.power.demo.util.DateTimeUtil;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;
import java.util.Date;
@Component
@EnableScheduling
public class SpringTaskB {

 /*fixedRate:上一次开始执行时间点之后5秒再执行*/
 @Scheduled(fixedRate = 5000)
 public void timerFixedRate() {
 try {
 Thread.sleep(100);
 } catch (Exception e) {
 e.printStackTrace();
 }
 System.out.println(String.format("(fixedRate)现在时间:%s", DateTimeUtil.fmtDate(new Date())));
 }

 /*fixedDelay:上一次执行完毕时间点之后5秒再执行*/
 @Scheduled(fixedDelay = 5000)
 public void timerFixedDelay() {
 try {
 Thread.sleep(100);
 } catch (Exception e) {
 e.printStackTrace();
 }
 System.out.println(String.format("(fixedDelay)现在时间:%s", DateTimeUtil.fmtDate(new Date())));

 }

 /*第一次延迟2秒后执行,之后按fixedDelay的规则每5秒执行一次*/
 @Scheduled(initialDelay = 2000, fixedDelay = 5000)
 public void timerInitDelay() {
 try {
 Thread.sleep(100);
 } catch (Exception e) {
 e.printStackTrace();
 }
 System.out.println(String.format("(initDelay)现在时间:%s", DateTimeUtil.fmtDate(new Date())));
 }
}
SpringTaskB

注意一下主要区别:

@Scheduled(fixedRate = 5000)  :上一次开始执行时间点之后5秒再执行

@Scheduled(fixedDelay = 5000)  :上一次执行完毕时间点之后5秒再执行

@Scheduled(initialDelay=2000, fixedDelay=5000)  :第一次延迟2秒后执行,之后按fixedDelay的规则每5秒执行一次

有时候,很多项目我们都需要配置好定时任务后立即执行一次,initialDelay就可以不用配置了。

3、zone

@Scheduled注解还有一个熟悉的属性zone,表示时区,通常,如果不写,定时任务将使用服务器的默认时区;如果你的任务想在特定时区特定时间点跑起来,比如常见的多语言系统可能会定时跑脚本更新数据,就可以设置一个时区,如东八区,就可以设置为:

zone = "GMT+8:00"

二、Quartz

Quartz是应用最为广泛的开源任务调度框架之一,有很多公司都根据它实现自己的定时任务管理系统。Quartz提供了最常用的两种定时任务触发器,即SimpleTrigger和CronTrigger,本文以最广泛使用的CronTrigger为例。

1、添加依赖

 <dependency>
 <groupId>org.quartz-scheduler</groupId>
 <artifactId>quartz</artifactId>
 <version>2.3.0</version>
 </dependency>

2、配置cron表达式

示例代码需要,在application.properties文件中新增如下配置:

## Quartz定时job配置
job.taska.cron=*/3 * * * * ?
job.taskb.cron=*/7 * * * * ?
job.taskmail.cron=*/5 * * * * ?

其实,我们完全可以不用配置,直接在代码里面写或者持久化在DB中然后读取也可以。

3、添加定时任务实现

任务1:

package com.power.demo.scheduledtask.quartz;
import com.power.demo.util.DateTimeUtil;
import org.quartz.DisallowConcurrentExecution;
import org.quartz.Job;
import org.quartz.JobExecutionContext;
import org.quartz.JobExecutionException;
import java.util.Date;

@DisallowConcurrentExecution
public class QuartzTaskA implements Job {
 @Override
 public void execute(JobExecutionContext var1) throws JobExecutionException {
 try {
 Thread.sleep(1);
 } catch (Exception e) {
 e.printStackTrace();
 }
 System.out.println(String.format("(QuartzTaskA)%s 每隔3秒执行一次,记录日志", DateTimeUtil.fmtDate(new Date())));
 }
}
QuartzTaskA

任务2:

package com.power.demo.scheduledtask.quartz;
import com.power.demo.util.DateTimeUtil;
import org.quartz.DisallowConcurrentExecution;
import org.quartz.Job;
import org.quartz.JobExecutionContext;
import org.quartz.JobExecutionException;
import java.util.Date;
@DisallowConcurrentExecution
public class QuartzTaskB implements Job {
 @Override
 public void execute(JobExecutionContext var1) throws JobExecutionException {
 try {
 Thread.sleep(100);
 } catch (Exception e) {
 e.printStackTrace();
 }
 System.out.println(String.format("(QuartzTaskB)%s 每隔7秒执行一次,记录日志", DateTimeUtil.fmtDate(new Date())));
 }
}
QuartzTaskB

定时发送邮件任务:

package com.power.demo.scheduledtask.quartz;
import com.power.demo.service.contract.MailService;
import com.power.demo.util.DateTimeUtil;
import com.power.demo.util.PowerLogger;
import org.joda.time.DateTime;
import org.quartz.DisallowConcurrentExecution;
import org.quartz.Job;
import org.quartz.JobExecutionContext;
import org.quartz.JobExecutionException;
import org.springframework.beans.factory.annotation.Autowired;
import java.util.Date;
@DisallowConcurrentExecution
public class MailSendTask implements Job {
 @Autowired
 private MailService mailService;
 @Override
 public void execute(JobExecutionContext var1) throws JobExecutionException {
 System.out.println(String.format("(MailSendTask)%s 每隔5秒发送邮件", DateTimeUtil.fmtDate(new Date())));
 try {
 //Thread.sleep(1);
 DateTime dtNow = new DateTime(new Date());
 Date startTime = dtNow.minusMonths(1).toDate();//一个月前
 Date endTime = dtNow.plusDays(1).toDate();
 mailService.autoSend(startTime, endTime);
 PowerLogger.info(String.format("发送邮件,开始时间:%s,结束时间:%s"
  , DateTimeUtil.fmtDate(startTime), DateTimeUtil.fmtDate(endTime)));

 } catch (Exception e) {
 e.printStackTrace();
 PowerLogger.info(String.format("发送邮件,出现异常:%s,结束时间:%s", e));
 }

 }
}
MailSendTask

实现任务看上去非常简单,继承Quartz的Job接口,重写execute方法即可。

4、集成Quartz定时任务

怎么让Spring自动识别初始化Quartz定时任务实例呢?这就需要引用Spring管理的Bean,向Spring容器暴露所必须的bean,通过定义Job Factory实现自动注入。

首先,添加Spring注入的Job Factory类:

package com.power.demo.scheduledtask.quartz.config;
import org.quartz.spi.TriggerFiredBundle;
import org.springframework.beans.factory.config.AutowireCapableBeanFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.scheduling.quartz.SpringBeanJobFactory;
public final class AutowireBeanJobFactory extends SpringBeanJobFactory
 implements ApplicationContextAware {
 private transient AutowireCapableBeanFactory beanFactory;

 /**
 * Spring提供了一种机制让你可以获取ApplicationContext,即ApplicationContextAware接口
 * 对于一个实现了ApplicationContextAware接口的类,Spring会实例化它的同时调用它的
 * public voidsetApplicationContext(ApplicationContext applicationContext) throws BeansException;接口,
 * 将该bean所属上下文传递给它。
 **/
 @Override
 public void setApplicationContext(final ApplicationContext context) {
 beanFactory = context.getAutowireCapableBeanFactory();
 }

 @Override
 protected Object createJobInstance(final TriggerFiredBundle bundle)
 throws Exception {
 final Object job = super.createJobInstance(bundle);
 beanFactory.autowireBean(job);
 return job;
 }
}
AutowireBeanJobFactory

定义QuartzConfig:

package com.power.demo.scheduledtask.quartz.config;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.quartz.CronTriggerFactoryBean;
import org.springframework.scheduling.quartz.SchedulerFactoryBean;

@Configuration
public class QuartzConfig {
 @Autowired
 @Qualifier("quartzTaskATrigger")
 private CronTriggerFactoryBean quartzTaskATrigger;
 @Autowired
 @Qualifier("quartzTaskBTrigger")
 private CronTriggerFactoryBean quartzTaskBTrigger;
 @Autowired
 @Qualifier("mailSendTrigger")
 private CronTriggerFactoryBean mailSendTrigger;
 //Quartz中的job自动注入spring容器托管的对象
 @Bean
 public AutowireBeanJobFactory autoWiringSpringBeanJobFactory() {
 return new AutowireBeanJobFactory();
 }

 @Bean
 public SchedulerFactoryBean schedulerFactoryBean() {
 SchedulerFactoryBean scheduler = new SchedulerFactoryBean();
 scheduler.setJobFactory(autoWiringSpringBeanJobFactory()); //配置Spring注入的Job类
 //设置CronTriggerFactoryBean,设定任务Trigger
 scheduler.setTriggers(
 quartzTaskATrigger.getObject(),
 quartzTaskBTrigger.getObject(),
 mailSendTrigger.getObject()
 );
 return scheduler;
 }
}
QuartzConfig

接着配置job明细:

package com.power.demo.scheduledtask.quartz.config;

import com.power.demo.common.AppField;
import com.power.demo.scheduledtask.quartz.MailSendTask;
import com.power.demo.scheduledtask.quartz.QuartzTaskA;
import com.power.demo.scheduledtask.quartz.QuartzTaskB;
import com.power.demo.util.ConfigUtil;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.quartz.CronTriggerFactoryBean;
import org.springframework.scheduling.quartz.JobDetailFactoryBean;
@Configuration
public class TaskSetting {

 @Bean(name = "quartzTaskA")
 public JobDetailFactoryBean jobDetailAFactoryBean() {
 //生成JobDetail
 JobDetailFactoryBean factory = new JobDetailFactoryBean();
 factory.setJobClass(QuartzTaskA.class); //设置对应的Job
 factory.setGroup("quartzTaskGroup");
 factory.setName("quartzTaskAJob");
 factory.setDurability(false);
 factory.setDescription("测试任务A");
 return factory;
 }

 @Bean(name = "quartzTaskATrigger")
 public CronTriggerFactoryBean cronTriggerAFactoryBean() {
 String cron = ConfigUtil.getConfigVal(AppField.JOB_TASKA_CRON);
 CronTriggerFactoryBean stFactory = new CronTriggerFactoryBean();
 //设置JobDetail
 stFactory.setJobDetail(jobDetailAFactoryBean().getObject());
 stFactory.setStartDelay(1000);
 stFactory.setName("quartzTaskATrigger");
 stFactory.setGroup("quartzTaskGroup");
 stFactory.setCronExpression(cron);
 return stFactory;
 }

 @Bean(name = "quartzTaskB")
 public JobDetailFactoryBean jobDetailBFactoryBean() {
 //生成JobDetail
 JobDetailFactoryBean factory = new JobDetailFactoryBean();
 factory.setJobClass(QuartzTaskB.class); //设置对应的Job
 factory.setGroup("quartzTaskGroup");
 factory.setName("quartzTaskBJob");
 factory.setDurability(false);
 factory.setDescription("测试任务B");
 return factory;
 }

 @Bean(name = "quartzTaskBTrigger")
 public CronTriggerFactoryBean cronTriggerBFactoryBean() {
 String cron = ConfigUtil.getConfigVal(AppField.JOB_TASKB_CRON);
 CronTriggerFactoryBean stFactory = new CronTriggerFactoryBean();
 //设置JobDetail
 stFactory.setJobDetail(jobDetailBFactoryBean().getObject());
 stFactory.setStartDelay(1000);
 stFactory.setName("quartzTaskBTrigger");
 stFactory.setGroup("quartzTaskGroup");
 stFactory.setCronExpression(cron);
 return stFactory;
 }

 @Bean(name = "mailSendTask")
 public JobDetailFactoryBean jobDetailMailFactoryBean() {
 //生成JobDetail
 JobDetailFactoryBean factory = new JobDetailFactoryBean();
 factory.setJobClass(MailSendTask.class); //设置对应的Job
 factory.setGroup("quartzTaskGroup");
 factory.setName("mailSendTaskJob");
 factory.setDurability(false);
 factory.setDescription("邮件发送任务");
 return factory;
 }

 @Bean(name = "mailSendTrigger")
 public CronTriggerFactoryBean cronTriggerMailFactoryBean() {
 String cron = ConfigUtil.getConfigVal(AppField.JOB_TASKMAIL_CRON);
 CronTriggerFactoryBean stFactory = new CronTriggerFactoryBean();
 //设置JobDetail
 stFactory.setJobDetail(jobDetailMailFactoryBean().getObject());
 stFactory.setStartDelay(1000);
 stFactory.setName("mailSendTrigger");
 stFactory.setGroup("quartzTaskGroup");
 stFactory.setCronExpression(cron);
 return stFactory;
 }
}
TaskSetting

最后启动你的Spring Boot定时任务应用,一个完整的基于Quartz调度的定时任务就实现好了。

本文定时任务示例中,有一个定时发送邮件任务MailSendTask,下一篇将分享Spring Boot应用中以MongoDB作为存储介质的简易邮件系统。

扩展阅读:

很多公司都会有自己的定时任务调度框架和系统,在Spring Boot中如何整合Quartz集群,实现动态定时任务配置?

参考:

//www.jb51.net/article/139591.htm

//www.jb51.net/article/139597.htm

总结

以上就是这篇文章的全部内容了,希望本文的内容对大家的学习或者工作具有一定的参考学习价值,如果有疑问大家可以留言交流,谢谢大家对脚本之家的支持。