用  java.util.Scanner 如下
	public static void main(String[] args) {
		while(true){
			Scanner scan = new Scanner(System.in);
			System.out.println("请输入：");
			String str = scan.next();
			if(!"q".equals(str)){
				System.out.println("输入："+str);
			}else {
				break;
			}
		}

	}
https://zhidao.baidu.com/question/339642195.html