public class Maths {
	
	public int factorial(int number) throws MathsException {
		if (number < 0) {
			MathsException e = new MathsException("Factorial of " + number + " not defined");
//			e.setX(100);
			throw e;
		}
		return number == 0 ? 1 : number * factorial(number - 1); 
	}
}