[news.eclipse.modeling.mdt.uml2] Re: Utility functions in the metaclasse

["James Bruck" <jbruck@xxxxxxxxxx>]

Hi Timothy,

The UML2 project makes use of PackageMerge to merge in additional operations 
not found in the metamodel but helpful to those using the API.
The UML spec also refers to "additional operations" that are sometimes 
required for OCL queries etc.  These could be added in the metamodel.

Cheers,
- James.

"Timothy Marc" <timothymarc@xxxxxxxxxx> wrote in message 
news:h1f8ck$hed$1@xxxxxxxxxxxxxxxxxxxx
> Hey all,
>
> just one question for a best practice. Which kind of operations should be 
> declared in a metamodel (e.g. getAllOwnedElemens() in the UML 
> Superstructure) and which kind should be imlemented in an external utility 
> package?
>
> In my case, i have a metamodel for an IOLTS (a directed graph) and for the 
> metaclasses Graph and State, there a several utility functions like 
> State::nextState(), Graph::getLastState() etc.
>
> Because i can't see the advantages respectively disadvantages of any of 
> these both solutions, i hope, that some of you modeling guys may serve any 
> hints for this questions. Is there any rule of thumb from the viewpoint of 
> the model driven paradigma, that says: This kind of operation is a "no go" 
> in a metamodel.... or something else :-)
>
> Thanks
> Timothy