Java学习 day65-71打卡

[令狐冲冲冲]

day71登录案例

package servlet;

/**
 * @author xpl
 * @code 2023-03-01 18:18
 */

import dao.UserDao;
import domain.User;

import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.annotation.*;
import java.io.IOException;

@WebServlet("/loginServlet")
public class LoginServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("utf-8");

        String username = request.getParameter("username");
        String password = request.getParameter("password");

        User loginUser = new User();
        loginUser.setUsername(username);
        loginUser.setPassword(password);

        UserDao userDao = new UserDao();
        User user = userDao.login(loginUser);


        if (user == null) {
            request.getRequestDispatcher("/failServlet").forward(request, response);
        }else {
            request.setAttribute("user",user);
            request.getRequestDispatcher("/successServlet").forward(request,response);

        }


    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this .doGet(request, response);

    }
}


package servlet;
/**
 * @author xpl
 * @code 2023-03-01 18:36
 */

import domain.User;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@WebServlet("/successServlet")
public class SuccessServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request,response);
    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        User user = (User) request.getAttribute("user");

        if(user != null) {
            response.setContentType("text/html;charset=utf-8");
            response.getWriter().write("登录成功" + user.getUsername());
        }
    }
}



package servlet;
/**
 * @author xpl
 * @code 2023-03-01 18:36
 */

import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.annotation.*;
import java.io.IOException;

@WebServlet("/failServlet")
public class FailServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request,response);
    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

        response.setContentType("text/html;charset=utf-8");
        response.getWriter().write("登陆失败，用户名或密码错误");
    }
}