Convert Roman to Integer and Vice Versa

RomanConvertor.java

/*
 Write a program to accept a number whuch is less than 50 and convert it into ROMAN form and vice versa.

 Eg:
    INPUT: 34
    OUTPUT: XXXIV

    INPUT: 50
    OUTPUT: Out of range

    INPUT: XXXVI
    OUTPUT: 36
*/

import java.util.Scanner;

class RomanConvertor {

    private boolean isRoman(String input) {
        String wordArray[] = new String[input.length()];

        for (int i = 0; i < input.length(); i++)
            wordArray[i] = input.substring(i, i + 1);

        for (int i = 0; i < wordArray.length; i++) {
            if (wordArray[i].equals("I") || wordArray[i].equals("V") || wordArray[i].equals("X"))
                continue;

            else
                return false;
        }

        return true;
    }

    private int convertToNumber(String str) {
        int number = 0;
        int i = 0;

        while (i < str.length()) {
            if (str.charAt(i) == 'I') {
                if (i + 1 < str.length() && str.charAt(i + 1) == 'V') {
                    number += 4;
                    i += 2;
                } else if (i + 1 < str.length() && str.charAt(i + 1) == 'X') {
                    number += 9;
                    i += 2;
                } else {
                    number += 1;
                    i++;
                }
            }

            else if (str.charAt(i) == 'V') {
                number += 5;
                i++;
            }

            else if (str.charAt(i) == 'X') {
                number += 10;
                i++;
            }

            else
                continue;
        }

        return number;
    }

    private String convertToRoman(int number) {
        String roman = "";

        while (number >= 10) {
            roman += "X";
            number -= 10;
        }

        if (number == 9) {
            roman += "IX";
            number -= 9;
        }

        while (number >= 5) {
            roman += "V";
            number -= 5;
        }

        if (number == 4) {
            roman += "IV";
            number -= 4;
        }

        while (number >= 1 && number < 4) {
            roman += "I";
            number -= 1;
        }

        return roman;
    }

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

        System.out.println("Enter the Number or Roman form");
        String str = sc.nextLine();

        str = str.toUpperCase();

        RomanConvertor obj = new RomanConvertor();

        if (obj.isRoman(str))
            System.out.println(obj.convertToNumber(str));

        else {
            int number = Integer.parseInt(str);

            if (number >= 50 || number < 1)
                System.out.println("Out of range");

            else
                System.out.println(obj.convertToRoman(number));
        }
    }
}