1.新建web项目

直接在web下面创建html文件

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>login</title>
</head>
<body>
<h2>用户登录</h2>
<form action="login" method="post">
    <table>
        <tr>
            <td>
                用户名:
            </td>
            <td>
                <input type="text" name="username">
            </td>
        </tr>
        <tr>
            <td>
                密码:
            </td>
            <td>
                <input type="password" name="pwd">
            </td>
        </tr>
        <tr>
            <td colspan="2">
                <input type="submit" value="登录">
            </td>
        </tr>
    </table>
</form>
</body>
</html>

3.LoginServlet

package servlet;

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;

/**
 * zt
 * 2020/8/29
 * 15:14
 */
@WebServlet(value = "/login")
public class LoginServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        //1处理乱码
        request.setCharacterEncoding("utf-8");
        response.setContentType("text/html;charset=utf-8");

        //2接收数据
        String username = request.getParameter("username");
        String pwd = request.getParameter("pwd");
        System.out.println(username+" "+pwd);
        //4直接判断
        if(username.equals("admin")&&pwd.equals("888")){
            //重定向到BooKList
            response.sendRedirect(" BookServlet");
        }else{
            //重定向
            response.sendRedirect("login.html");
        }
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doPost(request, response);
    }
}

4.运行结果

像我这样登陆成功跳转到BookServlet页面（response.sendRedirect(" BookServlet");），失败跳转回原界面（ response.sendRedirect(“login.html”);）

使用servlet完成简单的登录功能（servlet与html之间跳转（重定向））

1.新建web项目

2.login.html

3.LoginServlet

4.运行结果