public static function resolveConfigHandler($fileName)
    {
        $configHandler = NULL;

        preg_match("/(\.)([a-z]{3,})/", $fileName, $matches);

        $fileExtension = $matches[2];

        if (!in_array($fileExtension, ConfigConsts::getExtensions())) {
            throw new ConfigException("Not correct config file extension.");
        }

        switch ($fileExtension) {
            case(ConfigConsts::INI):
                $configHandler = new ConfigIniHandler();
                break;
            default:
                throw new ConfigException("Config handler wasn't set.");
        }

        return $configHandler;
    }