Poechant 练习 Java API - Y/N 输入验证

循环输入，直到控制台输入的内容为Y/y或N/n才结束，输入其他内容则提示错误。

import java.util.Scanner; public class test { public static void main(String[] args) { Scanner sc = new Scanner(System.in); boolean isValid = false; while (!isValid) { String str = sc.next(); if (str.equalsIgnoreCase("y")) { System.out.println("YES"); isValid = true; } else if (str.equalsIgnoreCase("n")) { System.out.println("NO"); isValid = true; } else { System.out.println("Please input \"y\" or \"n\""); } } } }