if (Strings.isNullOrEmpty(badWord)) {
            return "badWord was empty.";
        }
        if (badWord.contains(" ") || badWord.contains("  ")) {
            return "badWord contains space.";
        }
        return null;
    }

    /**
     * Update default bad words.
     */
    protected static void updateDefaultBadwords() {
        if (defaultWords != null) {