trigger critic instanc variabl initialis problem uninitialis instanc variabl look constructor param dm link java lang object object check critic param dsgr link argouml cognit design design creat model us futur develop argo uml link problem problem critic trigger link problem problem overrid predic object dm design dsgr look class model facad dm problem don consid secondari stuff model facad primari object dm problem type don need constructor model facad type dm problem util usual requir constructor model facad util dm problem check uninitialis instanc variabl constructor collect oper model facad oper dm iter oper oper iter oper model facad constructor oper constructor problem iter attr model facad attribut dm iter attr object attr attr model facad attr model facad initi attr non initi problem yeah right don oper problem 