public function deleteGroup($groupId)
{
$this->logger->logCall(__METHOD__, array('groupId' => $groupId));
$return = $this->persistenceHandler->objectStateHandler()->deleteGroup($groupId);
$this->cache->clear('objectstategroup', 'all');
$this->cache->clear('objectstategroup', $groupId);
$this->cache->clear('objectstate', 'byGroup', $groupId);
return $return;
}