protected function checkIfProtected($item)
    {
        $this->performProtectedCheck($item);

        if (!is_string($item)) {
            return;
        }

        $prefix = $item;
        while (false !== $pos = strrpos($prefix, '.')) {
            $prefix = substr($item, 0, $pos);
            $this->performProtectedCheck($prefix);
            $prefix = rtrim($prefix, '.');
        }
    }