class Player {

	public Player(String username) throws IllFormedPlayerException {
		if (username == null) {
			throw new NullPointerException();
		}
		
		if (username.length() != 8) {
			IllFormedPlayerException e = new IllFormedPlayerException("invalid length");
			throw e;
		}

	}

	public void sayHello() {
		System.out.println("Hello");
	}

}