PerfectSquare

import java.util.Scanner;

public class PerfectSquare {

    public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);

        System.out.println("Perfect square identifier (Enter -1 to quit program)");

        int userInput;

        do {
            System.out.print("Please enter a number: ");
            userInput = Integer.parseInt(sc.nextLine());
            if (!(perfectSquareIdentifier(userInput))) {
                System.out.printf("%,d is NOT a perfect square.\n", userInput);
            } else {
                System.out.printf("%,d is a perfect square.\n", userInput);
            }
        } while (userInput != -1);
    } // end main

    public static boolean perfectSquareIdentifier(int number) {
        if (number < 0) {
            return false;
        } else {
            double squareRootOfNumber = Math.sqrt(number);
            return ((squareRootOfNumber - Math.floor(squareRootOfNumber)) == 0);
        }
    }
}