public function getExtraOptionsHandler($extraOptionName)
    {
        // Check extraOption handlers that are valid for all classes
        if (isset(self::$extraOptionHandlers['*'][$extraOptionName])) {
            return self::$extraOptionHandlers['*'][$extraOptionName];
        }

        // Check extraOption handlers that are valid for the given class
        if (isset(self::$extraOptionHandlers[$this->class][$extraOptionName])) {
            return self::$extraOptionHandlers[$this->class][$extraOptionName];
        }

        return null;
    }