限制提示参数的数量

Question

I want to prompt the user to input just two numbers which represent the size NxN of a board. If the user write less than 1 or more than 2 numbers, the program don't allow him to do that and instead, handle this by an exception.

For example:

public class Tester {

public static void main(String[] args) {

    Scanner userInput = new Scanner(System.in);

    System.out.print("Board size NxN: ");

    int width = userInput.nextInt();
    int height = userInput.nextInt();
}
}

How can achieve this using a try-catch block limiting the user to input only 2 numbers?

Answer 1

public class Tester {

public static void main(String[] args) {

    Scanner userInput = new Scanner(System.in);

    System.out.print("Board size NxN: ");
    try {
        int width = userInput.nextInt();
        int height = userInput.nextInt();
        if (userInput.hasNext()) {
            throw new IllegalArgumentException();
        }
    } catch (IllegalArgumentException e) {
        System.err.println("Enter just two numbers");
    }
}

}