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Spring boot如何通过@Scheduled实现定时任务及多线程配置

2020-02-13 11:33 836 查看

这篇文章主要介绍了Spring boot如何通过@Scheduled实现定时任务及多线程配置,文中通过示例代码介绍的非常详细,对大家的学习或者工作具有一定的参考学习价值,需要的朋友可以参考下

使用@Scheduled 可以很容易实现定时任务

spring boot的版本 2.1.6.RELEASE

package com.abc.demo.common;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;
import java.text.SimpleDateFormat;
import java.util.concurrent.TimeUnit;
@EnableScheduling
@Component
public class ScheduleSetting {
private final Logger logger = LoggerFactory.getLogger(Tasks.class);
@Scheduled(fixedRate = 10000, initialDelay = 2000)
public void scheduleRead() {
try {
long timeStamp = System.currentTimeMillis();
SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Thread thread = Thread.currentThread();
System.out.println("cron1任务开始,start=" + simpleDateFormat.format(timeStamp) + ", threadId=" + thread.getId() + ", threadName=" + thread.getName());
long endStamp = System.currentTimeMillis();
try {
TimeUnit.SECONDS.sleep(20);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("cron1任务正在运行的线程名称:" + thread.getName() + " 结束,start=" + simpleDateFormat.format(timeStamp) + ",end=" + simpleDateFormat.format(endStamp));
System.out.println("++++++++++++++++++++++++");
} catch (Exception e) {
logger.error(e.getMessage());
}
}

@Scheduled(fixedRate = 5000, initialDelay = 1000)
public void scheduleConvert() {
try {

long timeStamp = System.currentTimeMillis();
SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Thread thread = Thread.currentThread();
System.out.println("cron2任务开始,start=" + simpleDateFormat.format(timeStamp) + ", threadId=" + thread.getId() + ", threadName=" + thread.getName());
try {
TimeUnit.SECONDS.sleep(10);
} catch (InterruptedException e) {
e.printStackTrace();
}
long endStamp = System.currentTimeMillis();
System.out.println("cron2任务正在运行的线程名称:" + thread.getName() + " 结束,start=" + simpleDateFormat.format(timeStamp) + ",end=" + simpleDateFormat.format(endStamp));
System.out.println("====================");
} catch (Exception e) {
logger.error(e.getMessage());
}
}
}

运行输出内容为

cron2任务开始,start=2019-10-11 17:31:52, threadId=34, threadName=scheduling-1
cron2任务正在运行的线程名称:scheduling-1 结束,start=2019-10-11 17:31:52,end=2019-10-11 17:32:02
====================
cron1任务开始,start=2019-10-11 17:32:02, threadId=34, threadName=scheduling-1
cron1任务正在运行的线程名称:scheduling-1 结束,start=2019-10-11 17:32:02,end=2019-10-11 17:32:02
++++++++++++++++++++++++
cron2任务开始,start=2019-10-11 17:32:22, threadId=34, threadName=scheduling-1
cron2任务正在运行的线程名称:scheduling-1 结束,start=2019-10-11 17:32:22,end=2019-10-11 17:32:32

……

注:

  cron2执行完后才会执行cron1

原因:

  spring默认是以单线程执行任务调度

  spring的定时任务默认最大运行线程数为1,多个任务执行起来时间会有问题

1.配置线程池

在配置文件application.properties中添加

# 线程池大小
spring.task.scheduling.pool.size=5
# 线程名前缀
spring.task.scheduling.thread-name-prefix=myScheduling-

输出内容变为

cron2任务开始,start=2019-10-11 17:34:48, threadId=34, threadName=myScheduling-1
cron1任务开始,start=2019-10-11 17:34:49, threadId=35, threadName=myScheduling-2
cron2任务正在运行的线程名称:myScheduling-1 结束,start=2019-10-11 17:34:48,end=2019-10-11 17:34:58
====================
cron2任务开始,start=2019-10-11 17:34:58, threadId=34, threadName=myScheduling-1
cron2任务正在运行的线程名称:myScheduling-1 结束,start=2019-10-11 17:34:58,end=2019-10-11 17:35:08
====================
cron2任务开始,start=2019-10-11 17:35:08, threadId=57, threadName=myScheduling-3
cron1任务正在运行的线程名称:myScheduling-2 结束,start=2019-10-11 17:34:49,end=2019-10-11 17:34:49

……

注:

多线程下,cron1和cron2不用互相等待了,但是同一个任务还是需要等待的

2.并发

修改代码

package com.abc.demo.common;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.scheduling.annotation.Async;
import org.springframework.scheduling.annotation.EnableAsync;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;
import java.text.SimpleDateFormat;
import java.util.concurrent.TimeUnit;
@EnableScheduling
@Component
@EnableAsync
public class ScheduleSetting {
private final Logger logger = LoggerFactory.getLogger(Tasks.class);
@Async
@Scheduled(fixedRate = 10000, initialDelay = 2000)
public void scheduleRead() {
try {
long timeStamp = System.currentTimeMillis();
SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Thread thread = Thread.currentThread();
System.out.println("cron1任务开始,start=" + simpleDateFormat.format(timeStamp) + ", threadId=" + thread.getId() + ", threadName=" + thread.getName());
long endStamp = System.currentTimeMillis();
try {
TimeUnit.SECONDS.sleep(20);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("cron1任务正在运行的线程名称:" + thread.getName() + " 结束,start=" + simpleDateFormat.format(timeStamp) + ",end=" + simpleDateFormat.format(endStamp));
System.out.println("++++++++++++++++++++++++");
} catch (Exception e) {
logger.error(e.getMessage());
}
}

@Async
@Scheduled(fixedRate = 5000, initialDelay = 1000)
public void scheduleConvert() {
try {

long timeStamp = System.currentTimeMillis();
SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Thread thread = Thread.currentThread();
System.out.println("cron2任务开始,start=" + simpleDateFormat.format(timeStamp) + ", threadId=" + thread.getId() + ", threadName=" + thread.getName());
try {
TimeUnit.SECONDS.sleep(10);
} catch (InterruptedException e) {
e.printStackTrace();
}
long endStamp = System.currentTimeMillis();
System.out.println("cron2任务正在运行的线程名称:" + thread.getName() + " 结束,start=" + simpleDateFormat.format(timeStamp) + ",end=" + simpleDateFormat.format(endStamp));
System.out.println("====================");
} catch (Exception e) {
logger.error(e.getMessage());
}
}
}

输出的内容

cron2任务开始,start=2019-10-11 17:39:53, threadId=57, threadName=task-1
cron1任务开始,start=2019-10-11 17:39:54, threadId=59, threadName=task-2
cron2任务开始,start=2019-10-11 17:39:58, threadId=61, threadName=task-3
cron2任务开始,start=2019-10-11 17:40:03, threadId=63, threadName=task-4
cron2任务正在运行的线程名称:task-1 结束,start=2019-10-11 17:39:53,end=2019-10-11 17:40:03
====================
cron1任务开始,start=2019-10-11 17:40:04, threadId=64, threadName=task-5
cron2任务开始,start=2019-10-11 17:40:08, threadId=65, threadName=task-6
cron2任务正在运行的线程名称:task-3 结束,start=2019-10-11 17:39:58,end=2019-10-11 17:40:08
====================
cron2任务开始,start=2019-10-11 17:40:13, threadId=66, threadName=task-7
cron2任务正在运行的线程名称:task-4 结束,start=2019-10-11 17:40:03,end=2019-10-11 17:40:13
====================
cron1任务正在运行的线程名称:task-2 结束,start=2019-10-11 17:39:54,end=2019-10-11 17:39:54

说明: 

  •   @EnableAsync开启多线程
  •   @Async标记其为一个异步任务
  •   每个定时任务都是在通过不同的线程来处理,线程名的前缀成了task-
  •   线程默认为10个

修改配置

spring.task.execution.thread-name-prefix=mytask-
spring.task.execution.pool.core-size=5

重新运行的输出

cron2任务开始,start=2019-10-11 17:44:00, threadId=56, threadName=mytask-1
cron1任务开始,start=2019-10-11 17:44:01, threadId=57, threadName=mytask-2
cron2任务开始,start=2019-10-11 17:44:05, threadId=58, threadName=mytask-3
cron2任务开始,start=2019-10-11 17:44:10, threadId=59, threadName=mytask-4
cron2任务正在运行的线程名称:mytask-1 结束,start=2019-10-11 17:44:00,end=2019-10-11 17:44:10
====================
cron1任务开始,start=2019-10-11 17:44:11, threadId=60, threadName=mytask-5
cron2任务正在运行的线程名称:mytask-3 结束,start=2019-10-11 17:44:05,end=2019-10-11 17:44:15
====================
cron2任务开始,start=2019-10-11 17:44:15, threadId=58, threadName=mytask-3
cron2任务开始,start=2019-10-11 17:44:20, threadId=56, threadName=mytask-1
cron2任务正在运行的线程名称:mytask-4 结束,start=2019-10-11 17:44:10,end=2019-10-11 17:44:20
====================
cron1任务正在运行的线程名称:mytask-2 结束,start=2019-10-11 17:44:01,end=2019-10-11 17:44:01

以上就是本文的全部内容,希望对大家的学习有所帮助

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