/**
  * Gets ACLs for given object identities
  *
  * @param SID $sid
  * @param OID[] $oids
  * @return \SplObjectStorage
  */
 protected function findAcls(SID $sid, array $oids)
 {
     try {
         return $this->manager->findAcls($sid, $oids);
     } catch (NotAllAclsFoundException $partial) {
         return $partial->getPartialResult();
     }
 }