java web 中 定时器的应用

package test;

import java.util.Timer;
import java.util.TimerTask;

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

public class TimerUtil implements ServletContextListener{
private Timer timer = null;

public void contextDestroyed(ServletContextEvent arg0) {
// TODO Auto-generated method stub
timer = new Timer();
timer.schedule(new TimerTask() {

@Override
public void run() {
// TODO Auto-generated method stub
System.out.println("定时器启动了！！！！！！！！！！");要执行的相关任务
}
},0,1*1000); //设置时间
}

public void contextInitialized(ServletContextEvent arg0) {
// TODO Auto-generated method stub
timer.cancel();
}

}

web.xml注册监听：

<listener>
<listener-class>test.TimerUtil </listener-class>
</listener>