question: private static void cleanStaleInitiatorReferences ( ExportGroup exportGroup , DbClient dbClient ) { StringSet exportGroupInitiators = exportGroup . getInitiators ( ) ; if ( ! CollectionUtils . isEmpty ( exportGroupInitiators ) && ! CollectionUtils . isEmpty ( exportGroup . getExportMasks ( ) ) ) { Set < String > allMaskInitiators = new HashSet < > ( ) ; for ( String mask : exportGroup . getExportMasks ( ) ) { ExportMask maskObj = dbClient . queryObject ( ExportMask . class , URI . create ( mask ) ) ; if ( maskObj != null && ! CollectionUtils . isEmpty ( maskObj . getInitiators ( ) ) ) { allMaskInitiators . addAll ( maskObj . getInitiators ( ) ) ; } } Set < String > staleInitiators = Sets . difference ( exportGroupInitiators , allMaskInitiators ) ; if ( ! CollectionUtils . isEmpty ( staleInitiators ) ) { Collection < URI > staleInitiatorURIS = Collections2 . transform ( staleInitiators , CommonTransformerFunctions . FCTN_STRING_TO_URI ) ; exportGroup . removeInitiators ( new ArrayList < > ( staleInitiatorURIS ) ) ; _log . info ( "Stale initiators {} will be removed from Export Group {}" , staleInitiatorURIS , exportGroup . getId ( ) ) ; } } }
target:  Cleans stale initiator references from export group instance