protected function getClassKey($entity)
    {
        $parts = explode('.', $entity);
        $class = array_shift($parts);

        // Ensure the `.ss` suffix gets added to the top level class rather than the key
        if (count($parts) > 1 && reset($parts) === 'ss') {
            $class .= '.ss';
            array_shift($parts);
        }
        $key = implode('.', $parts);
        return array($class, $key);
    }