Java Process Control 02 (Advanced Scanner Use)

Scanner advanced use
code (input and output integers and decimals)

package com.hao.scanner;

import java.util.Scanner;

public class Demo04 {
    public static void main(String[] args) {
        Scanner scanner =new Scanner (System.in);
        //从键盘接收数据
        int i=0;
        float f =0.0f;
        System.out.println("请输入整数：");
        if(scanner.hasNextInt()){
            i=scanner.nextInt();
            System.out.println("整数数据为："+i);
        }else{
            System.out.println("输入的不是整数数据！");
        }
        System.out.println("请输入小数数据：");
        if(scanner.hasNextFloat()){
            f=scanner.nextFloat();
            System.out.println("小数数据为："+f);
        }else{
            System.out.println("输入的不是小数数据！");
        }
        scanner.close();
    }
}

Output

code (input multiple numbers and find their sum and average)

package com.hao.scanner;

import java.util.Scanner;

public class Demo05 {
    public static void main(String[] args) {
        //我们可以输入多个数字，并求其总和与平均数，每输入一个数字用回车确认，通过输入非数字来结束输入并输出执行结果
        Scanner scanner =new Scanner(System.in);
        //和
        double sum =0.0;
        //计算输入了多少个数字
        int m=0;
        //通过循环哦按段是否还有输入，并在里面对每一次进行求和统计
        System.out.println("请输入数字，并用非数字来结束输入：");
        while(scanner.hasNextDouble()){
            double x = scanner.nextDouble();
            m++;
            sum+=x;
        }
        System.out.println(m+"个数的和为"+sum);
        System.out.println(m+"个数的平均值是"+sum/m);
        scanner.close();
    }
}

Output