web施用每晚12点定时执行程序代码实例

web应用每晚12点定时执行程序代码实例

1、当前web应用的web.xml文件配置容器监听类com.isoftstone.zfmi.listen.ZfmiContextListener：

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<listener>
?? <listener-class>
??? com.isoftstone.zfmi.listen.ZfmiContextListener
?? </listener-class>
</listener>

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在<filter-mapping>后，<servlet>元素之前

2、容器监听类com.isoftstone.zfmi.listen.ZfmiContextListener

在应用初始化和结束时，分别执行其覆盖的contextInitialized() 和contextDestroyed()方法，在contextInitialized()方法里，通过定时器timer的schedule(new FinDataTimerTask(),operTime, 86400000)方法在指定时间反复执行 FinDataTimerTask()对象中run()方法的操作，operTime 为指定初次执行时间，86400000)为反复执行时间间隔毫秒数，当前设定为一天，调试时可设短。

ZfmiContextListener.java:

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package com.isoftstone.zfmi.listen;

import java.io.IOException;
import java.util.Calendar;
import java.util.Date;
import java.util.Timer;

import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServlet;

import org.apache.log4j.Logger;

public class ZfmiContextListener extends HttpServlet implements
?? ServletContextListener {
Logger log = Logger.getLogger(this.getClass());
Timer timer = new Timer();

Date operTime;
public void service(ServletRequest request, ServletResponse response)
??? throws ServletException, IOException {//

}

public void contextInitialized(ServletContextEvent sce) {
?? log.info("\n 执行应用监听器初始方法????? initialcontext....");
??
?? Calendar now=Calendar.getInstance();
?? now.add(Calendar.DATE, 1);
?? now.set(Calendar.HOUR_OF_DAY, 0);
?? now.set(Calendar.MINUTE, 0);
?? now.set(Calendar.SECOND, 0);
?? now.set(Calendar.MILLISECOND, 0);
?? log.info("\n时间now为：?? "+now.toString()+"???? 毫秒数："+now.getTimeInMillis());
?? operTime=new Date(now.getTimeInMillis());
?? log.info("\n预设初始执行时间为：?? "+operTime);
?? timer.schedule(new FinDataTimerTask(),operTime, 86400000); //一天执行一次
//?? timer.schedule(new FinDataTimerTask(),operTime, 10000);?? //10秒钟执行一次,调试可用
}

public void contextDestroyed(ServletContextEvent sce) {
?? log.info("\n 执行应用监听器结束方法?????? destory context....");
?? timer.cancel();
}
}

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3、定时任务类com.isoftstone.zfmi.listen.FinDataTimerTask

继承TimerTask，需要定时执行的操作写在其覆盖的run()方法里面

FinDataTimerTask.java:

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package com.isoftstone.zfmi.listen;

import java.util.TimerTask;

import org.apache.log4j.Logger;

public class FinDataTimerTask extends TimerTask {
Logger log = Logger.getLogger(this.getClass());

public void run() {
?? //定时进行的操作
?? log.info("\n时间到，正在执行定时预设的操作....");
??
}
}

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