check transit part gener intern transit chosen test case instead transit state reason simplic param st state creat intern transit param text text pars param trigger expect trigger gener param guard expect guard gener param effect expect effect gener param except expect except thrown gener intern transit object check gener object st text trigger guard effect except object model state machin factori build intern transit st transit notat uml notat transit notat uml notat pars transit text expect except did happen except pars except unexpect except messag except trigger trigger gener text model facad trigger trigger gener text model facad trigger guard guard gener text model facad guard guard gener text model facad guard effect effect action gener text model facad effect effect action gener text model facad effect 