如何在SpringBoot中实现定时任务
如何在Spring Boot中实现定时任务?相信很多没有经验的人对此束手无策,为此本文总结了问题出现的原因和解决方法,通过这篇文章希望你能解决这个问题。
“只有客户发展了,才有我们的生存与发展!”这是创新互联的服务宗旨!把网站当作互联网产品,产品思维更注重全局思维、需求分析和迭代思维,在网站建设中就是为了建设一个不仅审美在线,而且实用性极高的网站。创新互联对成都网站设计、网站建设、网站制作、网站开发、网页设计、网站优化、网络推广、探索永无止境。
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
org.quartz-scheduler quartz 2.3.0
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
springboot是什么
springboot一种全新的编程规范,其设计目的是用来简化新Spring应用的初始搭建以及开发过程,SpringBoot也是一个服务于框架的框架,服务范围是简化配置文件。
看完上述内容,你们掌握如何在Spring Boot中实现定时任务的方法了吗?如果还想学到更多技能或想了解更多相关内容,欢迎关注创新互联行业资讯频道,感谢各位的阅读!
网页名称:如何在SpringBoot中实现定时任务
标题来源:http://scyanting.com/article/gechhh.html