java web 之简易登录

index.jsp

<%--
  Created by IntelliJ IDEA.
  User: ${陈平安}
  Date: 2022/6/3
  Time: 9:54
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>


    


<%=session.getAttribute("name02")
%>

 login.hsp

<%--
  Created by IntelliJ IDEA.
  User: ${陈平安}
  Date: 2022/6/3
  Time: 9:44
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>


    



    姓名：

    密码：

    

    ${msg}

Servlte03.java

package com.xxx.seervlet;

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 javax.servlet.http.HttpSession;
import java.io.IOException;


@WebServlet("/s04")
public class Servlet03 extends HttpServlet {
    @Override
    protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("UTF-8");
        String name = request.getParameter("name01");
        String pwd = request.getParameter("pwd01");
        if (name == null || name.trim().equals("") || pwd == null || pwd.trim().equals("")) {
            request.setAttribute("msg", "name or pwd cant be null");
            request.getRequestDispatcher("login.jsp").forward(request, response);
            return;
        }

        if ("admin".equals(name) && "123".equals(pwd)) {
            request.getSession().setAttribute("name02", name);
            response.sendRedirect("index.jsp");
            return;
        }else {
          //  request.setAttribute("msg", "error");
            request.setAttribute("msg", "fail");
            request.getRequestDispatcher("login.jsp").forward(request, response);
            return;
        }


   //     return;

    }
}