Re: Comparison : Ada and UML (comparison… indeed)

[Matteo Bordin <matteo.bordin@gmail.com>]

On Nov 9, 10:17 pm, "J-P. Rosen" <ro...@adalog.fr> wrote:
> Le 09/11/2010 18:44, Matteo Bordin a écrit :
>
> >> UML claims that it can represent any design method, thanks to stereotypes...
>
> > I think that what you really mean is to support the HOOD method using
> > UML. But to do so you would need to define a mapping between the
> > elements which the HOOD method requires to manipulate and UML
> > elements. This is not necessary straightforward/natural.
>
> You seem to think about using a UML tool to design in HOOD. I was more
> thinking of using UML notation in a HOOD tool (as STOOD does optionnaly)
>
> > You're right, sometimes I forgot that HOOD "models" does not have any
> > semantics... whatever UML box and arrow you pick, it will work...
>
> I guess you mean UML models use with HOOD... HOOD objects definitely
> have semantics!

Either HOOD is a language with an abstract syntax (a metamodel), or it
is not. It was you the one who said "HOOD is not a language".

Let's assume for a moment that HOOD has a semantics. If you want to
use a UML tool to apply the HOOD design methods, then you need to map
the HOOD abstract syntax (the metamodel) to the UML abstract syntax
(the UML metamodel). The mapping to the UML concrete syntax comes for
free because in UML the abstract and concrete syntax are coupled.

You suggest to use the UML notation on a HOOD tool to exploit the HOOD
method with a UML notation. This implies mapping the UML concrete (and
thus abstract) syntax to HOOD concepts. Again, this requires a
semantic mapping between the two languages. It is on the
appropriateness of this mapping that I have doubts. For whatever
reason you seem to perceive this as a critique to HOOD.

Anyway, you cite STOOD as an exemplary tool. Please go here (http://
www.hurray.isep.ipp.pt/ae2006/pdfs/Tuesday/Vendor_Sessions/ellidiss.pdf)
at look at slide 8. Do you understand that someone made a decision of
mapping the notion of HOOD object to UML.Property? Do you understand
that this is a semantic mapping meaning implying that a HOOD object
and a UML.Property are equivalent? What is the rationale behind this
decision? For example, HRT-UML originally made a different choice.
This is the point: in STOOD the use of UML/AADL/HOOD/HRT-HOOD is
purely a skin with no semantic meaning at all. The abstract syntax is
always the same; what changes is just the concrete syntax. Note that
the same comments can be made for the AADL view...