SpringMVC实现强制登录

1、登录部分代码

@RequestMapping("/login.do")
    public String login(User user,HttpSession session){
        boolean login = us.login(user);
        if(login){
            String realname = us.queryRealname(user);
            session.setAttribute("realname", realname);
            session.setAttribute("flag", "ok");            
            Date date = new Date();
            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); 
            String time = sdf.format(date.getTime());
            session.setAttribute("date", time);
            return "redirect:/stu/queryAll.do";
        }
        return "user/login";
    }

2、拦截器部分代码

@Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response,
            Object arg2) throws Exception {
        HttpSession session = request.getSession();
        if("ok".equals(session.getAttribute("flag"))){
            return true;
        }
        else{
            response.sendRedirect("/SMS2.0/user/login.jsp");
            return false;
        }
    }

3、spring_mvc.xml拦截器配置部分代码

<mvc:interceptors>
        <mvc:interceptor>
            <!-- 拦截的范围 -->
            <!-- 过滤指定请求 -->
            <mvc:mapping path="/stu/*"/>
            <!-- 排除不过滤的请求 -->
            <mvc:exclude-mapping path="/user/*"/>
            <!-- 拦截器实现类 -->
            <bean class="com.baizhi.interceptor.SmsInterceptor"></bean>
        </mvc:interceptor>
    </mvc:interceptors>