counterlistener.java

来自「介绍了j2ee开发常用的学习知识,如servlet,javamail,EJB等知」· Java 代码 · 共 40 行

/*
 * CounterListener.java
 *
 * Created on 2007年10月19日, 下午4:15
 */

package com.servlet;

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

public class CounterListener implements ServletContextListener {
    
     String path="";
    public void contextInitialized(ServletContextEvent evt) {
         
         CounterFile f=new CounterFile();
         String name=evt.getServletContext().getInitParameter("CounterPath");
         path=evt.getServletContext().getRealPath(name);
         try{
         String temp=f.ReadFile(path);
         System.out.println(temp);
         evt.getServletContext().setAttribute("Counter",temp);//将计数器的值放入应用上下文
         }catch(Exception e){
             System.out.println(e.toString());
         }
         
    }
    public void contextDestroyed(ServletContextEvent evt) {
         try{
         String  current= (String)evt.getServletContext().getAttribute("Counter");
       
         CounterFile f=new CounterFile();
         f.WriteFile(path,current);
         }catch(Exception e){
             System.out.println(e.toString());
         }
    }
}