Scanner 的进阶使用

package com.wang.scenner;

import java.util.Scanner;

public class Demo03 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入整数：");
        int i=0;
        float f = 0.0f;
        if(scanner.hasNextInt()){
            i = scanner.nextInt();
            System.out.println("输出的整数："+ i);
        }else
            System.out.println("输入的数不是整数");


        System.out.println("请输入小数：");

        if(scanner.hasNextFloat()){
            f = scanner.nextFloat();
            System.out.println("输出的小数："+ f);
        }else
            System.out.println("输入的数不是小数");
        scanner.close();
    }
}

package com.wang.scenner;

import java.util.Scanner;

public class Demo04 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输出数据");
        double sum= 0;
        int m=02;
        while (scanner.hasNextDouble()){
            //输入的数据不是Double类型时台哦出循环
            double a = scanner.nextDouble();
            m++;//m=m+1;
            sum+=a;//sum
            System.out.println("你输入了第"+m+"数据，当前的和为"+sum);
        }
        System.out.println(m+"个数的和为"+sum);
        System.out.println(m+"个数的平均值"+(sum/m));
        scanner.close();
    }
}