From: Les Munday (email@example.com)
Date: Thu 13 Jun 2002 - 19:48:24 BST
________________________________________________ Get your own "800" number Voicemail, fax, email, and a lot more http://www.ureach.com/reg/tag ---- On Thu, 13 Jun 2002, Ulf Schuenemann (firstname.lastname@example.org) wrote: > From the state modeling side, Harel (father of StateCharts) and Gery > ["Executable Object Modeling with Statecharts" Computer 30(7) July > 1997, early version in ICSE'96] are only concerned with composite > objects. They accept (weak) aggregation only for consistency with > UML. They describe the semantics of UML's aggregation (wrt. state > modeling?) as being ``essentially just that of a special > association.'' Preferable would be a more explicit statement like > "aggregation is irrelevant to state modeling" (but maybe it isnt't?). > [NB also for composition Harel+Gery do not mention constraints on states] > And I agree. I was object modeling long before UML came on the scene and I had no special notation for aggregation nor composition. As someone pointed out to me when I first discovered composition, 'is this not just a special type of association with a cardinality of exactly 1 on the "whole" end?'. Les.