狂神说 javaweb 32集：smbms注销及权限过滤_SMBMS 项目搭建（三）

32. smbms注销及权限过滤

登录功能优化

注销功能;

思路：移除session，返回登录页面

LogoutServlet.java

 package com.study.servlet.user;
 
 import com.study.util.Constants;
 
 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import java.io.IOException;
 
 public class LogoutServlet extends HttpServlet {
     @Override
     protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
         //移除用户session
         req.getSession().removeAttribute( Constants.USER_SESSION );
         resp.sendRedirect( req.getContextPath()+"/login.jsp" );//返回登录页面
 
     }
 
     @Override
     protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
         doGet( req, resp );
     }
 }

注册xml

 <servlet>
         <servlet-name>LogoutServlet</servlet-name>
         <servlet-class>com.study.servlet.user.LogoutServlet</servlet-class>
     </servlet>
     <servlet-mapping>
         <servlet-name>LogoutServlet</servlet-name>
         <url-pattern>/jsp/logout.do</url-pattern>
     </servlet-mapping>

登录拦截优化

SysFilter.java

 package com.study.filter;
 
 
 import com.study.pojo.User;
 import com.study.util.Constants;
 
 import javax.servlet.*;
 import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import java.io.IOException;
 
 public class SysFilter implements Filter {
     public void init(FilterConfig filterConfig) throws ServletException {
 
     }
 
     public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws IOException, ServletException {
         HttpServletRequest request = (HttpServletRequest) req;
         HttpServletResponse response = (HttpServletResponse) resp;
 
         //过滤器。从session中获取用户，
         User user = (User) request.getSession().getAttribute( Constants.USER_SESSION );
 
         if(user == null){//已经被移除或者注销了
             response.sendRedirect( "/smbms/login.jsp" );
         }else{
             chain.doFilter( request,response );
         }
     }
 
     public void destroy() {
 
     }
 }

xml

 <!--用户登录过滤器-->
 <filter>
     <filter-name>SysFilter</filter-name>
     <filter-class>com.study.filter.SysFilter</filter-class>
 </filter>
 <filter-mapping>
     <filter-name>SysFilter</filter-name>
     <url-pattern>/jsp/*</url-pattern>
 </filter-mapping>