sessionlistener.java

一个基于java工厂模式的 的实现

/*
 * SessionListener.java
 *
 * Created on 2007年4月28日, 下午1:46
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */

package com.ebuy.web.listeners;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpSession;
import javax.servlet.http.HttpSessionEvent;

/**
 *
 * @author Administrator
 */
public class SessionListener implements javax.servlet.http.HttpSessionListener
{
    
    /** Creates a new instance of SessionListener */
    public SessionListener()
    {
    }

    public void sessionCreated(HttpSessionEvent se)
    {
        HttpSession session=se.getSession();
        ServletContext context=session.getServletContext();
        int total=Integer.parseInt(context.getAttribute("total").toString());
        total ++;
        context.setAttribute("total",total);
        session.setAttribute("index",total);
        
        int online=Integer.parseInt(context.getAttribute("online").toString());
        online++;
        context.setAttribute("online",online);
    }

    public void sessionDestroyed(HttpSessionEvent se)
    {
        ServletContext context=se.getSession().getServletContext();
        int online=Integer.parseInt(context.getAttribute("online").toString());
        online--;
        context.setAttribute("online",online);
    }
    
}