我每次刷新server.jsp网页都会被拦截，这个怎么处理？

    我修改了一下代码，所以没有那种情况出现了

我项目中明明有啊，还看了压缩包也有的，老师那里没有吗？

没看懂老师这里说的取一次是什么？是存入session的属性吗？

但是浏览器关闭，代表这个session销毁，只剩下cookie了啊。。。

package com.imooc.filter;

import java.io.IOException;

import java.util.List;

import javax.servlet.Filter;

import javax.servlet.FilterChain;

import javax.servlet.FilterConfig;

import javax.servlet.ServletException;

import javax.servlet.ServletRequest;

import javax.servlet.ServletResponse;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

import com.imooc.entity.User;

import com.imooc.utility.LibServiceImpl;

public class LoginFilter implements Filter {

@Override

public void destroy() {

// TODO Auto-generated method stub

}

@Override

public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)

throws IOException, ServletException {

HttpServletRequest hrequest=(HttpServletRequest)request;

HttpServletResponse hresponse=(HttpServletResponse)response;

//获取参数

String username=hrequest.getParameter("username");

String password=hrequest.getParameter("password");

// System.out.println("username:"+username+"\tpassword:"+password);

LibServiceImpl serviceImpl=new LibServiceImpl();

int flag=serviceImpl.login(username, password);

System.out.println("flag:"+flag);

if(flag==1) {

//登录成功,获取用户信息并存入session

HttpSession session=hrequest.getSession();

List<User> list =serviceImpl.getDaoImpl().getUserdb();

for (User u : list) {

if(u.getUsername().equals(username)){

session.setAttribute("User", u);

}

}

chain.doFilter(request, response);

return;

}else if (username.equals("")&&password.equals("")) {

hresponse.sendRedirect(hrequest.getContextPath()+"/index.jsp?flag=4");

return;

}

else {

hresponse.sendRedirect(hrequest.getContextPath()+"/index.jsp?flag=3");

return;

}

}

@Override

public void init(FilterConfig filterConfig) throws ServletException {

// TODO Auto-generated method stub

}

}