protected function getParametersFromNode($node, $parameterName = 'parameter')
    {
        if (null === $node) {
            return [];
        }

        $parameters = [];
        foreach ($this->xpath->query('x:' . $parameterName, $node) as $parameterNode) {
            $name = $this->xpath->query('@name', $parameterNode)->item(0)->nodeValue;
            $parameters[$name] = $parameterNode->nodeValue;
        }

        return $parameters;
    }