Java Scanner

Class Scanner
   java.lang.Object
      java.util.Scanner
All Implemented Interfaces:
Closeable, AutoCloseable, Iterator

其他不说，实现了Iterator接口

boolean  hasNext()
                Returns true if the iteration has more elements.

E    next()

        Returns the next element in the iteration.

Scanner scan = new Scanner(System.in);

String name = scan.nextLine();//回车结束输入，计入空格，是一行输入

int age = scan.nextInt();//空格结束，键盘键入有效数字开始，
//如果键入  abc（非数字字符会报错）所以有 hasNextInt();

String name = scan.next(); //输入一行如果以空格间隔，只会取到空格之前的字符，后面并不会取到。

实列：输入数字以0结束

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0

import java.util.Scanner;
Scanner scan = new Scanner(System.in);
        String str = "";
        int i = 1;
        do{
                i = scan.nextInt();
            str += i;
        }while( i != 0);
        System.out.println(str);

输入两个数 n和b

import java.util.Scanner;
Scanner scan = new Scanner(System.in);
        int n = 0 ;
        int  b = 0;
        n = scan.nextInt();
        b = scan.nextInt();
        scan.close();
        System.out.println(n +b);