PhoneNumber.java

/**
 * Created by RupGautam on 2/21/17.
 */

import java.util.Scanner;
public class PhoneNumber {



//  2047773333, (204)777-3333, or 204-777-333

    public static boolean isValidNumber(String number) {
      boolean validLength = number.length() == 10 || number.length() == 12 || number.length() == 11;

      boolean firstValidString =
          number.charAt(0) == '(' && number.charAt(4) == ')' && number.charAt(8) == '-';
      boolean secondValidString = number.charAt(3) == '-' && number.charAt(7) == '-';

      return validLength || firstValidString || secondValidString;
    }


    public static void main(String[] args) {
      System.out.println("Enter you phone number");
      Scanner scanner = new Scanner(System.in);
      String input;
      while (!(input = scanner.next()).equals("exit")) {
        if(isValidNumber(input)) {
          System.out.println("Valid number");
        }else {
          System.out.println("Invalid number");
        }

        System.out.println("Enter your phone number");
      }
    }
  }