如何使用Java为用户登录创建类？

public class User {
    private String username;
    private String password;

    public User(String username, String password) {
        this.username = username;
        this.password = password;
    }

    // Getters and setters

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }
}

public class LoginServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String username = request.getParameter("username");
        String password = request.getParameter("password");

        // 假设存在一个名为userService的服务类，用于处理用户相关操作
        UserService userService = new UserService();

        // 调用userService的方法进行用户登录验证
        boolean loginSuccess = userService.login(username, password);

        if (loginSuccess) {
            // 登录成功
            response.sendRedirect("home.jsp");
        } else {
            // 登录失败
            response.sendRedirect("login.jsp?error=1");
        }
    }
}

<form action="LoginServlet" method="post">
    <input type="text" name="username" placeholder="用户名" required>
    <input type="password" name="password" placeholder="密码" required>
    <button type="submit">登录</button>
</form>