Spring mvc 实现用户登录的方法(拦截器)

package cn.woniubushiniu.controller;

import cn.woniubushiniu.po.user;

import org.springframework.stereotype.controller;

import org.springframework.ui.model;

import org.springframework.web.bind.annotation.requestmapping;

import org.springframework.web.bind.annotation.requestmethod;

import javax.servlet.http.httpsession;

@controller

public class usercontroller {

   /**

    * 向用户登录页面跳转

    */

   @requestmapping (value = "/login" ,method = requestmethod.get)

   public string tologin(){

     return "login" ;

   }

   /**

    * 用户登录

    * @param user

    * @param model

    * @param session

    * @return

    */

   @requestmapping (value = "/login" ,method = requestmethod.post)

   public string login(user user, model model, httpsession session){

     //获取用户名和密码

     string username=user.getusername();

     string password=user.getpassword();

     //些处横板从数据库中获取对用户名和密码后进行判断

     if (username!= null &&username.equals( "admin" )&&password!= null &&password.equals( "admin" )){

       //将用户对象添加到session中

       session.setattribute( "user_session" ,user);

       //重定向到主页面的跳转方法

       return "redirect:main" ;

     }

     model.addattribute( "msg" , "用户名或密码错误，请重新登录！" );

     return "login" ;

   }

   @requestmapping (value = "/main" )

   public string tomain(){

     return "main" ;

   }

   @requestmapping (value = "/logout" )

   public string logout(httpsession session){

     //清除session

     session.invalidate();

     //重定向到登录页面的跳转方法

     return "redirect:login" ;

   }

}

public class logininterceptor implements handlerinterceptor {

   @override

   public boolean prehandle(httpservletrequest request, httpservletresponse response, object o) throws exception {

     //获取请求的rui:去除http:localhost:8080这部分剩下的

     string uri = request.getrequesturi();

     //utl:除了login.jsp是可以公开访问的，其他的url都进行拦截控制

     if (uri.indexof( "/login" ) >= 0 ) {

       return true ;

     }

     //获取session

     httpsession session = request.getsession();

     user user = (user) session.getattribute( "user_session" );

     //判断session中是否有用户数据，如果有，则返回true，继续向下执行

     if (user != null ) {

       return true ;

     }

     //不符合条件的给出提示信息，并转发到登录页面

     request.setattribute( "msg" , "您还没有登录，请先登录！" );

     request.getrequestdispatcher( "/web-inf/jsp/login.jsp" ).forward(request, response);

     return false ;

   }

   @override

   public void posthandle(httpservletrequest httpservletrequest, httpservletresponse httpservletresponse, object o, modelandview modelandview) throws exception {

   }

   @override

   public void aftercompletion(httpservletrequest httpservletrequest, httpservletresponse httpservletresponse, object o, exception e) throws exception {

   }

}

<!--登录拦截器-->

     <mvc:interceptor>

       <mvc:mapping path= "/**" />

       <bean class = "cn.woniubushiniu.interceptor.logininterceptor" />

     </mvc:interceptor>

   </mvc:interceptors>

<!--配置前端控制器-->

   <servlet>

     <servlet-name>springmvc</servlet-name>

     <servlet- class >org.springframework.web.servlet.dispatcherservlet</servlet- class >

     <init-param>

       <param-name>contextconfiglocation</param-name>

       <param-value>classpath:springmvc-config.xml</param-value>

     </init-param>

     <load-on-startup> 1 </load-on-startup>

   </servlet>

   <servlet-mapping>

     <servlet-name>springmvc</servlet-name>

     <url-pattern>/</url-pattern>

   </servlet-mapping>