public function storeWebfilesFromStream(MWebfileStream $webfileStream)
    {

        if ($this->isReadOnly()) {
            throw new MDatastoreException("cannot modify data on read-only datastore.");
        }

        $webfiles = $webfileStream->getWebfiles();
        foreach ($webfiles as $webfile) {
            $this->storeWebfile($webfile);
        }
    }