Scanner

Scanner

next():

遇到空格，会当作结束符。

import java.util.Scanner;

public class Demo01 {

    public static void main(String[] args) {
        //
        Scanner sc = new Scanner(System.in);
        System.out.println("Please input:"); //Hello World

        if(sc.hasNext()){
            // 接收输入
            String str = sc.next();
            System.out.println(str); // Hello
        }

        //凡事IO类的，用完要关掉，节省资源
        sc.close();
    }
}

nextLine()：

以Enter为结束符，可以获得呃空白

import java.util.Scanner;

public class Demo02 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        System.out.println("Input:"); // Hello World

        if(sc.hasNextLine()){
            String s = sc.nextLine();
            System.out.println(s); // Hello World
        }

        sc.close();
    }
}

总和和平均值

package com.Chris.scanner;

import java.util.Scanner;

public class Demo04 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        double sum = 0;
        int m =0;

        while(scanner.hasNextDouble()){
            double x = scanner.nextDouble();
            m++;
            sum += x;
        }

        System.out.println(sum);
        System.out.println(sum/m);

        scanner.close();

    }
}