instanc classifi belong return vector set vector set uml sequenc diagram fig object fig compon instanc fig node instanc classifi param sd diagram check set offend list set comput offend uml sequenc diagram sd collect fig sd layer content list set off object obj fig obj fig node model element fig node model element fn fig node model element obj fn model facad instanc fn owner object minst fn owner minst collect col model facad classifi minst col size off off list set off add sd off add fn off 