package com.he.login;

import java.util.HashMap;
import java.util.Map;

import javax.servlet.http.HttpSession;
import javax.servlet.http.HttpSessionAttributeListener;
import javax.servlet.http.HttpSessionBindingEvent;
/**
 * 用于监听session属性的添加
 * 
 * @author 何锦彬    QQ 277803242
 *
 */
public class LoginListener implements HttpSessionAttributeListener {
    // 已经登录用户session
    public static Map<String, HttpSession> loginedUser = new HashMap<String, HttpSession>();

    public void attributeAdded(HttpSessionBindingEvent eventAdd) {
        // TODO 监听session属性的添加
        String attrName = eventAdd.getName();
        // 监听到为属性userName的添加
        if ("userName".equals(attrName)) {
            String value = (String) eventAdd.getValue();
            HttpSession session = loginedUser.get(value);
            if (session != null) {
                session.removeAttribute(attrName);
            }
            loginedUser.put(value, eventAdd.getSession());
        }

    }

    public void attributeRemoved(HttpSessionBindingEvent arg0) {
        // TODO Auto-generated method stub

    }

    public void attributeReplaced(HttpSessionBindingEvent arg0) {
        // TODO Auto-generated method stub

    }

}