J2EE实现计划任务

第一步：创建一个任务监听类，实现ServletContextListener 接口

import java.util.Calendar;
import java.util.Timer;

import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import javax.servlet.http.HttpServlet;

/**
 * @author dym
 *
 */
public class ScheduleTaskListener extends HttpServlet implements ServletContextListener{
 
   private static final long serialVersionUID = 7065236947173387428L; 
  

     
     //设置启动时间为2点45; 
     private static final int hours = 14; 
     private static final int minutes = 45;
     private static final int seconds = 0; 
      
     //设置间隔时间为10秒; 
     private static final long interval = 10 * 1000;    
     //定时器; 
     private static Timer timer=new Timer(); 
      
     public void contextDestroyed(ServletContextEvent sce) { 
         System.out.println("ScheduleTaskListener>>stop"); 
         timer.cancel();
     } 
  
     public void contextInitialized(ServletContextEvent sce) { 
          System.out.println("-------定时工作开启");
             System.out.println("ScheduleTaskListener>>start"); 
             Calendar calendar = Calendar.getInstance();      
             calendar.set(Calendar.HOUR_OF_DAY, hours); 
             calendar.set(Calendar.MINUTE, minutes); 
             calendar.set(Calendar.SECOND, seconds);     
             timer.schedule(new ScheduleTask(),calendar.getTime(),interval); 
     }    

}

第二步：创建一个时间任务类

import java.util.TimerTask;

public class ScheduleTask extends TimerTask {

    public void run() { 
            System.out.println("ScheduleTaskListener is running!"); 
    } 
 
}

第三步：在web中添加一个监听器


web.xml里的配置
<listener>  

<listener-class>  

    tax.lite.wf.ws.nsfw.task.ScheduleTaskListener

</listener-class>  

</listener>