java 监听器

1、首先配置web.xml文件
      <listener>   
          <listener-class>cn.com.spcs.ots.common.util.OverTimeSystemListener</listener-class>
      </listener>
2、实现ServletContextListener接口
    contextInitialized(final ServletContextEvent arg0)
    contextDestroyed(ServletContextEvent arg0)
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.Map;
import java.util.Timer;
import java.util.TimerTask;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import cn.com.cs.ots.bean.dao.DB2DAOImpl;
import cn.com.cs.ots.bean.dao.IDAO;
import cn.com.cs.ots.common.Constant;
/**
* 加班休假系统批处理启动
*
* @author
*/
public class OverTimeSystemListener implements ServletContextListener {
private Timer timer = null;
private TimerTask task = null;
protected IDAO dao;
private int executeCount = 0;
// 月份变量
private static int month = 1;
// 日期变量
private static int day = 1;
// 分钟变量
private static int minute = 1;
// 小时变量
private static int hour = 1;
// 秒变量
private static int second = 1;
/**
* 加班休假系统监听方法contextInitialized
*
* @param arg0
*
* 备注<br>
* 作者： 作成日：2008-10-22<br>
*/
public void contextInitialized(final ServletContextEvent arg0) {
SysLogger.info(this, "contextInitialized is start.");
timer = new Timer();
task = new TimerTask() {
public void run() {
try {
GregorianCalendar date = new GregorianCalendar();
month = date.get(Calendar.MONTH);
day = date.get(Cal