案例开发-日程管理3(用过滤器控制登录校验)

过滤器控制登录校验

需求说明:未登录状态下不允许访问showShedule.html和SysScheduleController相关增删改处理,重定向到login.html,登录成功后可以自由访问

开发登录过滤器,对指定资源的请求进行过滤

java 复制代码

import jakarta.servlet.*;
import jakarta.servlet.annotation.WebFilter;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import jakarta.servlet.http.HttpSession;

import java.io.IOException;

@WebFilter(urlPatterns = {"/showSchedule.html","/schedule/*"})
public class LoginFilter  implements Filter {
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request =(HttpServletRequest) servletRequest;
        HttpServletResponse response =(HttpServletResponse) servletResponse;
        HttpSession session = request.getSession();
        Object sysUser = session.getAttribute("sysUser");
        if(null != sysUser){
            // session中如果存在登录的用户 代表用户登录过,则放行
            filterChain.doFilter(servletRequest,servletResponse);

        }else{
            //用户未登录,重定向到登录页
            response.sendRedirect("/login.html");
        }
    }
}

修改用户登录请求的login方法,登录成功时,将用户信息存入session

java 复制代码

 /**
     * 用户登录的业务接口
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    protected void login(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 接收用户请求参数
        // 获取要注册的用户名密码
        String username = req.getParameter("username");
        String userPwd = req.getParameter("userPwd");
        // 调用服务层方法,根据用户名查询数据库中是否有一个用户
        SysUser loginUser =userService.findByUsername(username);
        if(null == loginUser){
            // 没有根据用户名找到用户,说明用户名有误
            resp.sendRedirect("/loginUsernameError.html");
        }else if(! loginUser.getUserPwd().equals(MD5Util.encrypt(userPwd))){
            // 用户密码有误,
            resp.sendRedirect("/loginUserPwdError.html");
        }else{
            // 登录成功,将用户信息存入session
            req.getSession().setAttribute("sysUser",loginUser);
            // 登录成功,重定向到日程展示页
            resp.sendRedirect("/showSchedule.html");
        }
    }