doe cascad delet modelel associ element illeg state delet element doe cascad delet element delet mdr method remov method call directli classifi follow element ul li associ end classifi type ul param elem uml factori mdr impl delet object delet classifi object elem elem classifi illeg argument except elem elem model impl uml helper delet collect model impl facad associ end elem classifi cl classifi elem delet creat action instanti model impl uml helper delet collect omg uml uml cl ref outermost common behavior creat action instanti creat action cl todo delet instanc classifi leav contain state user recreat nsmodel uml helper delet collect nsmodel uml common behavior instanc classifi instanc cl todo delet object flow state type nsmodel uml helper delet collect nsmodel uml activ graph type object flow state object flow state cl todo delet classifi state type model impl uml helper delet collect omg uml uml cl ref outermost activ graph type classifi state classifi state cl 