question: public Long deleteRoom ( Rooms r ) { log . debug ( "deleteRoom" ) ; try { r . setDeleted ( "true" ) ; r . setUpdatetime ( new Date ( ) ) ; if ( r . getRooms_id ( ) == null ) { em . persist ( r ) ; } else { if ( ! em . contains ( r ) ) { em . merge ( r ) ; } } return r . getRooms_id ( ) ; } catch ( Exception ex2 ) { log . error ( "[deleteRoomsOrganisation] " , ex2 ) ; } return null ; }
target:  deletes a Room by given Room-Object