超市订单管理系统SMBMS - 注销以及权限过滤功能实现

登录功能优化

注销功能：

Servlet代码xml注册 登录拦截优化

编写一个过滤器xml注册过滤器

思路：移除session，返回登录页面

package com.yang.servlet.user;

import com.yang.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 {
        //移除用户的session
        req.getSession().removeAttribute(Constants.USER_SESSION);
        resp.sendRedirect("/login.jsp");//返回登录页面
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
}

    
        LogoutServlet
        com.yang.servlet.user.LogoutServlet
    
    
        LogoutServlet
        /jsp/logout.do
    

package com.yang.filter;

import com.yang.pojo.User;
import com.yang.util.Constants;

import javax.servlet.*;
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;

        //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,或者未登录
            response.sendRedirect("smbms/error.jsp");
        }else {
            chain.doFilter(req,resp);
        }
    }

    public void destroy() {

    }
}

    
        SysFilter
        com.yang.filter.SysFilter
    
    
        SysFilter
        /jsp/*