三十九 SpringBoot定时任务-Scheduled定时任务

一、Scheduled定时任务

Scheduled定时任务器：是Spring3.0以后自带的一个定时任务器。

二 创建项目：25-spring-boot-scheduled

三 修改pom.xml

注意：在spring-boot-starter-web启动器中并没有添加Scheduled定时任务器，所以需要另外添加。

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>2.1.3.RELEASE</version>
	</parent>
	<groupId>com.bjsxt</groupId>
	<artifactId>25-spring-boot-schuduled</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	
	<properties>
		<java.version>1.8</java.version>
		<tymeleaf.version>3.0.2.RELEASE</tymeleaf.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-thymeleaf</artifactId>
		</dependency>
		<!-- 添加Scheduled坐标 -->
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-context-support</artifactId>
		</dependency>
	</dependencies>
</project>

四 编写定时任务类

package com.bjsxt.scheduled;

import java.util.Date;

import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;

/**
 * scheduled定时任务
 *
 */
@Component
public class ScheduledDemo {
	/**
	 * 定时任务方法
	 * @Scheduled:设置定时任务
	 * cron属性：cron表达式，定时任务触发时间的字符串表达形式
	 */
	@Scheduled(cron="0/2 * * * * ?")
	public void scheduledMethod() {
		System.out.println("定时器被触发" +  new Date());
	}
}

五 在启动类中开启定时任务的使用

package com.bjsxt;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.scheduling.annotation.EnableScheduling;

@SpringBootApplication
@EnableScheduling
public class App {
	public static void main(String[] args) {
		SpringApplication.run(App.class, args);
	}
}

执行结果： 

定时器被触发Mon Apr 22 16:37:30 CST 2019
定时器被触发Mon Apr 22 16:37:32 CST 2019
定时器被触发Mon Apr 22 16:37:34 CST 2019
定时器被触发Mon Apr 22 16:37:36 CST 2019
定时器被触发Mon Apr 22 16:37:38 CST 2019
定时器被触发Mon Apr 22 16:37:40 CST 2019