private function getOwnInterfaces($class, $parent)
    {
        $ownInterfaces = class_implements($class, false);

        if ($parent) {
            foreach (class_implements($parent, false) as $interface) {
                unset($ownInterfaces[$interface]);
            }
        }

        foreach ($ownInterfaces as $interface) {
            foreach (class_implements($interface) as $interface) {
                unset($ownInterfaces[$interface]);
            }
        }

        return $ownInterfaces;
    }