static public function validateResource(Resource $res, Fedora $fedora): array {
        $results = array();
        foreach ($res->propertyUris() as $prop) {
            if ($prop === self::RDFS_TYPE) {
                $tmp = self::checkClass($res, $fedora);
            } else {
                $tmp = self::checkProperty($prop, $res, $fedora);
            }
            $results = array_merge($results, $tmp);
        }
        return $results;
    }