Spring Boot(七)：springboot的定时任务

谁践踏了优雅 2022-01-23 14:47 208阅读 0赞

springboot定时任务就非常简单！

1、添加依赖：引入 Spring Boot Starter 包即可

<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

2、在启动类上加上注解@EnableScheduling启用定时

//开启调度任务
    @EnableScheduling

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzE5MTY3NjI5_size_16_color_FFFFFF_t_70][]

3、创建定时任务的实现类

这里我做了两个demo

a、

package cn.tycoding.timer;
    
    import org.springframework.scheduling.annotation.Scheduled;
    import org.springframework.stereotype.Component;
    
    /**
     * @Author: lilong
     * @Data: Created on 2019/6/4
     * @Desc: 定时任务1
     */
    @Component
    public class SchedulerTask {
        private int count = 0;
        @Scheduled(cron = "*/6 * * * * ?")
        private  void process(){
            System.out.println(""+(count++));
        }
    }

b、

package cn.tycoding.timer;
    
    import org.springframework.scheduling.annotation.Scheduled;
    import org.springframework.stereotype.Component;
    
    import java.text.SimpleDateFormat;
    import java.util.Date;
    
    /**
     * @Author: lilong
     * @Data: Created on 2019/6/4
     * @Desc: 定时任务2
     */
    @Component
    public class Scheduler2Task {
        private static final SimpleDateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
    
        @Scheduled(fixedRate = 6000)
        public void reportCurrentTime(){
            System.out.println("现在的时间："+dateFormat.format(new Date()));
        }
    }

运行结果如下：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzE5MTY3NjI5_size_16_color_FFFFFF_t_70 1][]

再后面补充一些springboot定时器相关的用法代码

package com.lilong.tasks;
    
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.scheduling.annotation.Scheduled;
    import org.springframework.stereotype.Component;
    
    import java.text.SimpleDateFormat;
    import java.util.Date;
    
    
    /**
     * @Author: lilong
     * @Data: Created on 2019/9/5
     * @Desc: 创建定时任务
     */
    @Component
    public class ScheduledTasks {
        private static final Logger log = LoggerFactory.getLogger(ScheduledTasks.class);
    
        private static final SimpleDateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
    
        //通过在方法上加@Scheduled注解，表明该方法是一个调度任务。
        @Scheduled(fixedRate = 5000)//上一次开始执行时间点之后5秒再执行
        public void  reportCurrentTime(){
            log.info("上一次开始执行时间点之后5秒再执行的时间:{}",dateFormat.format(new Date()));
        }
        @Scheduled(fixedDelay = 5000)
        public void reportCurrentTime2(){
            log.info("上一次执行完毕时间点之后5秒再执行的时间 -- The time to reexecute 5 seconds after the last execution point:{}",dateFormat.format(new Date()));
        }
        @Scheduled(initialDelay = 1000,fixedDelay = 5000)
        public void reportCurrentTime3(){
            log.info("第一次延迟1秒后执行，之后按fixedRate的规则每5秒执行一次时间:{}",dateFormat.format(new Date()));
        }
        @Scheduled(cron = "*/6 * * * * ?")//cron表达式
        public void reportCurrentTime4(){
            log.info("自行搜索引擎的时间 -- Cron expression:{}",dateFormat.format(new Date()));
        }
    }

运行结果：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzE5MTY3NjI5_size_16_color_FFFFFF_t_70 2][]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzE5MTY3NjI5_size_16_color_FFFFFF_t_70]: /images/20220123/faed56cefd9348df8eb005e57f87930b.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzE5MTY3NjI5_size_16_color_FFFFFF_t_70 1]: /images/20220123/879c8d3cf5de45b2a1b354da8a973c37.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzE5MTY3NjI5_size_16_color_FFFFFF_t_70 2]: /images/20220123/7a05a5caff1d4a73afb864b9ef62ab78.png