Spring boot如何通过@Scheduled实现定时任务及多线程配置

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

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