参考答案

import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class JAVA {
public static void main(String[] args) {
    String regEx = "\\D+";
    Scanner in = new Scanner(System.in);
    while (in.hasNext()) {
        String str = in.next();
        Pattern p = Pattern.compile(regEx);
        Matcher m = p.matcher(str);
        if (!m.find()) {
            System.out.println("输入的字符串全是数字");
        } else {
            System.out.println("输入的字符串不全是数字");
        }
      }
    }
}