JAVA WEB项目定时执行任务

1.创建类实现接口 ServletContextListener

2.实现方法contextInitialized（初始化）和contextDestroyed（销毁）

package com.baosight.webapp.util;

import java.util.Date;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;


public class SaveFile implements ServletContextListener {


@Override
public void contextDestroyed(ServletContextEvent arg0) {
System.out.println("+++++++++++++++++++Game Over");

}

@Override
public void contextInitialized(ServletContextEvent arg0) {
Runnable runnable = new Runnable() {
            public void run() {
                // task to run goes here
            System.out.println("============time:"+new Date());
                System.out.println("Hello !!");
            }
        };
        ScheduledExecutorService service = Executors
                .newSingleThreadScheduledExecutor();
        System.out.println(new Date());
        //第一个参数是触发事件s，第二个参数是执行延迟时间s，第三个参数是时间间隔
        service.scheduleAtFixedRate(runnable, 1, 10, TimeUnit.SECONDS);

}
public static void main(String[] args) {
Date date=new Date();
//下周一0点据当前时间的秒数
int interval = (7 - date.getDay() + 1)*24*3600 - date.getHours()*3600 - date.getMinutes()*60 - date.getSeconds();

}
}

3.web.xml文件监听类

 <listener>
<listener-class>com.baosight.webapp.util.SaveFile</listener-class>
</listener>