public function setConfigFile($configFile = '')
    {
        if (!is_readable($configFile)) {
            $this->activeConfig = [];

            throw ParserException::forFileUnreadable($configFile);
        }

        $this->configFile = $configFile;
        if (!$this->parseConfigFile()) {
            throw InvalidConfigException::forEmptyConfig($configFile);
        }

        return $this;
    }