如何使输入读出一行中的多个整数？

Question

How can I make it so that I can prompt the user to input multiple integers on one line that are seperated by spaces. And if the first integer is 0 or less than 0 it will print out "Bad Input" when all the integers are inputted and the user presses enter. Also how can I make it so that when the user enters a negative number at the end of the line, it will stop entering numbers and make multiply all of them together.

This is what I have so far but i'm not sure I am doing this right.

import java.util.Scanner;

public class tempprime {

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

        int count = 1;

        String inputnumbers;
        System.out.print("Enter integers: ");
        inputnumbers = input.nextLine();
        for (int i = 0; i < inputnumbers.length(); i++){
            if (inputnumbers.charAt(i) == ' ')
                count++;

        }
        int[] numbers = new int[count];

    }

}

Answer 1

You already have it so the user can enter in values until they hit enter. Now you can do is use a split operation to break the string up into an array of values.

String[] values = inputnumbers.split('\s'); 

Then you could replace charAt with access to the array.

Alternatively, Scanner already allows the user to enter in as many integers as they need on the same line. nextLine() finds the first occurance of a new line, but you can use input.nextInt(), grabs the next int stopping at a space, multiple times and read them in one at a time. You can also check if there are any more values remaining using the scanners hasNext methods.

https://docs.oracle.com/javase/7/docs/api/java/util/Scanner.html

You can see an example of reading multiple ints below. The user can enter them in one at a time, or 3 at a time and should still work the same.

    Scanner in = new Scanner(System.in);

    System.out.print("Enter 3 ints:");
    int a,b,c;
    a = in.nextInt();
    b = in.nextInt();
    c = in.nextInt();
    System.out.printf("A: %d B: %d C: %d", a, b ,c);