Tomcat 定时器 Timer

小乔

/**
* TimerTaskCount.java
* com.linkage.util
*
* Function： TODO
*
*   ver     date      author
* ──────────────────────────────────
*    Mar 10, 2010 chengYu
*
* Copyright (c) 2010,  All Rights Reserved.
*/
package com.linkage.util.count;
/**
* ClassName:TimerTaskCount
* Project:
* Company: LINKAGE
*
* @author   chengYu
* @version  
* @since    Ver 1.1
* @Date Mar 10, 20104:47:34 PM
*
* @see  
*/
import java.util.Timer;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class TimerTaskCount implements ServletContextListener
{
private final static Logger log = LoggerFactory.getLogger(TimerTaskCount.class);
private Timer timer = null;
public void contextInitialized(ServletContextEvent event)
{
log.info("-----------------监听器启动-----------------------");
//在这里初始化监听器，在tomcat启动的时候监听器启动，可以在这里实现定时器功能
timer = new Timer(true);
log.info("---------------------------------------------------");
event.getServletContext().log("定时器已启动");//添加日志，可在tomcat日志中查看到
timer.schedule(new exportHistoryBean(event.getServletContext()),0l,(60*60*1000));
//    调用exportHistoryBean，0表示任务无延迟，5*1000表示每隔5秒执行任务，60*60*1000表示一个小时。
event.getServletContext().log("已经添加任务");
}
public void contextDestroyed(ServletContextEvent event)
{
//在这里关闭监听器，所以在这里销毁定时器。
timer.cancel();
event.getServletContext().log("定时器销毁");
}
}

/**
* exportHistoryBean.java
* com.linkage.util.count
*
* Function： TODO
*
*   ver     date      author
* ──────────────────────────────────
*    Mar 10, 2010 chengYu
*
* Copyright (c) 2010,  All Rights Reserved.
*/
package com.linkage.util.count;
/**
* ClassName:exportHistoryBean
* Project:
* Company: LINKAGE
*
* @author   chengYu
* @version  
* @since    Ver 1.1
* @Date Mar 10, 20105:15:18 PM
*
* @see  
*/
import java.util.Calendar;
import java.util.TimerTask;
import javax.servlet.ServletContext;
public class exportHistoryBean extends TimerTask
{
private static final int C_SCHEDULE_HOUR = 0;
private static boolean isRunning = false;
private ServletContext context = null;
public exportHistoryBean(ServletContext context)
{
this.context = context;
}
public void run()
{
Calendar c = Calendar.getInstance();
if(!isRunning)
{
if(C_SCHEDULE_HOUR == c.get(Calendar.HOUR_OF_DAY))
{
isRunning = true;
context.log("开始执行指定任务");
//-------------------开始保存当日历史记录

//在这里编写自己的功能，例：
//File file = new File("temp");
//file.mkdir();
//启动tomcat，可以发现在tomcat根目录下，会自动创建temp文件夹
//-------------------结束
isRunning = false;
context.log("指定任务执行结束");
}
else
{
context.log("上一次任务执行还未结束");
}
}
}
}

web.xml
<!-- 定时器 -->
<listener>
<listener-class>com.linkage.util.count.TimerTaskCount</listener-class>
</listener>