private boolean areRegistrationCredentialsValid(Player player, String retypedPassword) {
		boolean valid = false;

		if (player.getFirstName().isEmpty()) {
			MMessageBox.show(REGISTRATION_FIRST_NAME_EMPTY);
			this.firstName.setValid(valid);
		} else if (player.getLastName().isEmpty()) {
			MMessageBox.show(REGISTRATION_LAST_NAME_EMPTY);
			this.lastName.setValid(valid);
		} else if (player.getUsername().isEmpty()) {
			MMessageBox.show(REGISTRATION_USERNAME_EMPTY);
			this.username.setValid(valid);
		} else if (player.getPassword().isEmpty()) {
			MMessageBox.show(REGISTRATION_PASSWORD_EMPTY);
			this.password.setValid(valid);
		} else if (retypedPassword.isEmpty()) {
			MMessageBox.show(REGISTRATION_PASSWORD_RETYPED_EMPTY);
			this.passwordRetype.setValid(valid);
		} else if (!player.getPassword().equals(retypedPassword)) {
			MMessageBox.show(REGISTRATION_PASSWORD_RETYPED_INVALID);
			this.passwordRetype.setValid(valid);
		} else if (player.getEmail().isEmpty()) {
			MMessageBox.show(REGISTRATION_EMAIL_EMPTY);
			this.email.setValid(valid);
		} else if (!this.isEmailValid(player.getEmail())) {
			MMessageBox.show(REGISTRATION_EMAIL_IS_INVALID);
			this.email.setValid(valid);
		} else {
			valid = true;
		}
		
		return valid;
	}