如何用Java编写一个非常简单的用户登录代码？

import java.util.Scanner;

public class UserLogin {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        System.out.print("请输入用户名：");
        String username = scanner.nextLine();

        System.out.print("请输入密码：");
        String password = scanner.nextLine();

        String presetUsername = "admin";
        String presetPassword = "password";

        if (username.equals(presetUsername) && password.equals(presetPassword)) {
            System.out.println("登录成功！");
        } else {
            System.out.println("登录失败！");
        }

        scanner.close();
    }
}