Re: isa and hasa in UML

----- Original Message ----- 
From: "Francis McCabe" <fgm@fla.fujitsu.com>
To: "Walden Mathews" <waldenm@optonline.net>
Cc: <www-ws-arch@w3.org>
Sent: Friday, May 30, 2003 4:25 PM
Subject: Re: isa and hasa in UML

Frank,

I've *elided* most of the beginning of this message (that's
an UML term, isn't it?).  My basic feeling is: take a stab with UML,
using folks comfortable with it, and assess where you are, as opposed
to objecting to it on such theoretical grounds (birds and all...)

I was surprised to hear that the WS's identifier was not necessarily
the service's identifier, even though "service" is in this case just a
more generic way of referring to the WS.  If that's true, then it's an
"architecture smell", not a modeling problem, IMO.  But if models
bring that kind of thing "to the nostril", then bravo to the models.

I don't like "counts-as" because it equivocates about roles, and
a model ought to be clarifying in that area, not equivocating.  X either
identifies Y or it doesn't.  That's all I care about.


> Can you provide a pointer to Alloy?

Gladly.
http://sdg.lcs.mit.edu/alloy/

> In general, I think that we could use UML. However, the feeling that I 
> get is that somehow UML `solves' the modeling question. I wish that 
> that were true; but it doesn't. Furthermore, the UML community has 
> really resisted becoming formal; I was pretty disappointed in the lack 
> of interest personally.

I have found in my experience that formal models have their
audience, and that audience is not as wide as one might prefer,
but that's the way it is.  The goal here is broad (if imprecise)
communication, I believe.  The best tool is the one that does that,
formal or not.

Walden

Received on Friday, 30 May 2003 18:08:51 UTC