The FlexSession is invalid问题

package com.cmbj.soa.servicemonitor.view.service.impl;



import java.util.Enumeration;



import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;



import flex.messaging.HttpFlexSession;

import flex.messaging.MessageBrokerServlet;



public class KMessageBrokerServlet extends MessageBrokerServlet {

	@Override

	public void service(HttpServletRequest req, HttpServletResponse res) { 

		HttpSession httpSession = req.getSession(true);

		HttpFlexSession flexSession = (HttpFlexSession)httpSession.getAttribute("__flexSession");

		if( flexSession != null && !flexSession.isValid()){  

			httpSession.removeAttribute("__flexSession");  

		} 

//		HttpSession httpSession = req.getSession(true);

//		

//		Enumeration<String> names = httpSession.getAttributeNames();

//		String name = null;

//		for (;  names.hasMoreElements();) {

//			name = names.nextElement();

//			if (httpSession.getAttribute(name) instanceof HttpFlexSession) {

//				HttpFlexSession flexSession = (HttpFlexSession) httpSession.getAttribute(name);

//				if(null != flexSession && !flexSession.isValid()){

//					httpSession.setAttribute(name,null);

//					httpSession.removeAttribute(name);

//				}

//				System.out.println("HttpFlexSession_name is " + name);

//			}

//		}

		super.service(req, res);

	}

}

重写MessageBrokerServlet的service方法，因为异常的源头来自该servlet用了一个invalid的HttpFlexSession去获取Principal，所以只要再service方法之前先判断下当前的HttpFlexSession是否已经无效，无效的话我们就从当前的HttpSession中移除这个无效的HttpFlexSession即可。这样，就能保证MessageBrokerServlet中所用的HttpFlexSession一定是有效的