SpringBoot定时任务多线程实现示例

SpringBoot定时任务多线程实现示例

测试Spring Boot定时任务冲突时，使用的线程数量

引入依赖：

Spring Boot 2.6.1

org.projectlombok

lombok

简单的测试类

import lombok.extern.slf4j.Slf4j;

import org.springframework.scheduling.annotation.Scheduled;

import org.springframework.stereotype.Component;

/**

* @author Song Jiangtao

* @date 2021/12/22

* @description:

*/

@Component

@Slf4j

public class Task {

@Scheduled(cron="*/2 * * * * ?")

public void process(){

log.info("do something");

}

@Scheduled(fixedRate = 2000)

public void currentTime(){

log.info("做点什么");

}

}

启动类开启定时任务：@EnableScheduling

测试结果如下：

由结果可见，main线程启动以后和scheduling-1线程跑了两个任务

由此可见，Spring Boot 定时器 默认是 单线程

我们新增两个定时任务来看看这样会有什么后果

@Scheduled(cron="*/2 * * * * ?")

public void process2() throws InterruptedException {

Thread.sleep(5000L);

log.info("do something use long time");

}

@Scheduled(cron="*/2 * * * * ?")

public void process3() throws InterruptedException {

Thread.sleep(10000L);

log.info("do something use long long time");

}

2021-12-22 16:30:28.735 INFO 14520 --- [ main] c.e.s.SpringBootScheduledApplication nKTCjbxgT : Starting SpringBootScheduledApplication using java 1.8.0_202 on TCZ-D with PID 14520 (D:\code\SpringBootScheduled\target\classes started by Administrator in D:\code\SpringBootScheduled)

2021-12-22 16:30:28.738 INFO 14520 --- [ main] c.e.s.SpringBootScheduledApplication : No active profile set, falling back to default profiles: default

2021-12-22 16:30:29.315 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做点什么

2021-12-22 16:30:29.318 INFO 14520 --- [ main] c.e.s.SpringBootScheduledApplication : Started SpringBootScheduledApplication in 0.937 seconds (JVM running for 3.068)

2021-12-22 16:30:30.002 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : do something

2021-12-22 16:30:40.003 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : do something use long long time

2021-12-22 16:30:45.005 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : do something use long time

2021-12-22 16:30:45.005 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做点什么

2021-12-22 16:30:45.005 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : do something

2021-12-22 16:30:45.006 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做点什么

2021-12-22 16:30:45.006 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做点什么

2021-12-22 16:30:45.006 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做点什么

2021-12-22 16:30:45.006 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做点什么

2021-12-22 16:30:45.006 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做点什么

2021-12-22 16:30:55.006 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : do something use long long time

2021-12-22 16:30:55.006 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做点什么

2021-12-22 16:30:55.006 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做点什么

2021-12-22 16:30:55.007 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : do something

很明显任务会发生错乱，严重时会导致线程阻塞，最后崩溃

解决方法：引入线程池

新增配置类，配置线程池

package com.example.springbootscheduled.config;

import org.springframework.context.annotation.Bean;

import org.springframework.context.annotation.Configuration;

import org.springframework.scheduling.annotation.EnableAsync;

import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;

import java.util.concurrent.ThreadPoolExecutor;

/**

* @author Song Jiangtao

* @date 2021/12/22

* @description:

*/

@Configuration

@EnableAsync

public class TaskConfig {

/**

* 默认线程数

*/

private static final int corePoolSize = 10;

/**

* 最大线程数

*/

private static final int maxPoolSize = 100;

/**

* 允许线程空闲时间（单位：默认为秒）,十秒后就把线程关闭

*/

private static final int keepAliveTime = 10;

/**

* 缓冲队列数

*/

private static final int queueCapacity = 200;

/**

* 线程池名前缀

*/

private static final String threadNamePrefix = "task-thread-";

/**

* bean的名称，默认为 首字小写 方法名

*/

@Bean("taskExecutor")

public ThreadPoolTaskExecutor getThread() {

ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();

executor.setCorePoolSize(corePoolSize);

executor.setMaxPoolSize(maxPoolSize);

executor.setQueueCapacity(keepAliveTime);

executor.setKeepAliveSeconds(queueCapacity);

executor.setThreadNamePrefix(threadNamePrefix);

//线程池拒绝策略

executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());

executor.initialize();

return executor;

}

}

每个定时任务添加注解 @Async("taskExecutor")

@Async("taskExecutor")

@Scheduled(fixedRate = 2000)

public void currentTime(){

log.info("做点什么");

}

启动测试

2021-12-22 16:41:36.141 INFO 19424 --- [ main] c.e.s.SpringBootScheduledApplication : Starting SpringBootScheduledApplication using Java 1.8.0_202 on TCZ-D with PID 19424 (D:\code\SpringBootScheduled\target\classes started by Administrator in D:\code\SpringBootScheduled)

2021-12-22 16:41:36.143 INFO 19424 --- [ main] c.e.s.SpringBootScheduledApplication : No active profile set, falling back to default profiles: default

2021-12-22 16:41:36.991 INFO 19424 --- [ main] c.e.s.SpringBootScheduledApplication : Started SpringBootScheduledApplication in 1.325 seconds (JVM running for 3.392)

2021-12-22 16:41:37.008 INFO 19424 --- [ task-thread-1] c.e.springbootscheduled.scheduled.Task : 做点什么

2021-12-22 16:41:38.001 INFO 19424 --- [ task-thread-2] c.e.springbootscheduled.scheduled.Task : do something

2021-12-22 16:41:38.991 INFO 19424 --- [ task-thread-5] c.e.springbootscheduled.scheduled.Task : 做点什么

2021-12-22 16:41:40.003 INFO 19424 --- [ task-thread-8] c.e.springbootscheduled.scheduled.Task : do something

2021-12-22 16:41:40.991 INFO 19424 --- [ task-thread-9] c.e.springbootscheduled.scheduled.Task : 做点什么

2021-12-22 16:41:42.001 INFO 19424 --- [ task-thread-10] c.e.springbootscheduled.scheduled.Task : do something

2021-12-22 16:41:42.989 INFO 19424 --- [ task-thread-5] c.e.springbootscheduled.scheduled.Task : 做点什么

2021-12-22 16:41:43.002 INFO 19424 --- [ task-thread-3] c.e.springbootscheduled.scheduled.Task : do something use long time

2021-12-22 16:41:44.002 INFO 19424 --- [ task-thread-9] c.e.springbootscheduled.scheduled.Task : do something

2021-12-22 16:41:44.990 INFO 19424 --- [ task-thread-5] c.e.springbootscheduled.scheduled.Task : 做点什么

2021-12-22 16:41:45.002 INFO 19424 --- [ task-thread-6] c.e.springbootscheduled.scheduled.TanKTCjbxgTsk : do something use long time

2021-12-22 16:41:46.001 INFO 19424 --- [ task-thread-9] c.e.springbootscheduled.scheduled.Task : do something

2021-12-22 16:41:46.990 INFO 19424 --- [ task-thread-6] c.e.springbootscheduled.scheduled.Task : 做点什么

2021-12-22 16:41:47.002 INFO 19424 --- [ task-thread-1] c.e.springbootscheduled.scheduled.Task : do something use long time

2021-12-22 16:41:48.002 INFO 19424 --- [ task-thread-4] c.e.springbootscheduled.scheduled.Task : do something use long long time

版权声明：本文内容由网络用户投稿，版权归原作者所有，本站不拥有其著作权，亦不承担相应法律责任。如果您发现本站中有涉嫌抄袭或描述失实的内容，请联系我们jiasou666@gmail.com 处理，核实后本网站将在24小时内删除侵权内容。