Adding digit of an integer upto single digit sum

import java.util.Scanner;

public class AddDigitUpToSingleDigit {

public static void main(String[] arg) {

Scanner in = new Scanner(System.in);

System.out.print("Input a positive integer: ");

int n = in.nextInt();

if (n>0)

{

System.out.print("The single digit number is: "+(n == 0 ? 0 :

                                (n % 9 == 0 ? 9 : n % 9)));

}

System.out.println("\n");

}

}