No, you'd need to use GJ API to retrieve the group object after pulling groupid from the URL. Example as follows.
Code:
$group = cbgjData::getGroups( null, array( 'id', '=', (int) $id ), null, null, false );
Replace $id with the id of the group you want. That'll give its class object. GJ needs to be present on the page you're executing this on or at least its class file included first.