v15.2 – Multiple Extension doesn’t aggregate the attributes

[Paolo F Cantoni]

The Extension relationship in profile models is used to provide additional properties to the generated stereotype via attributes defined in the metaclass.

Sometimes we extend more than one metaclass.  We expected the attributes to be aggregated, but this doesn't seem to be the case.  Is this a defect?  If not why not?  (Just asking for clarification)

Paolo

[Eve]

Multiple extensions provide the options for which types a stereotype can be applied to, they aren't intended (by either UML or Enterprise Architect) to combine the referenced metaclasses.

In UML terms, an extension is an association between the stereotype and the metaclass, applying a stereotype is creating an instance of the stereotype with the instance of the association specifying which element typed by the original metaclass the stereotype instance is applied to.

[qwerty]

Ever since we found out that extending multiple metaclasses from a stereotype means that you can not use individual stereotype properties we are avoiding such a construct. We only have a few multi-extensions left over where we're pretty sure that we never will need any stereotype properties. In the first design it was a neat idea to have one stereotype to bind them all (Tolkien told me so) but then we wanted a diagram property for one metaclass which did not make sense for the other. Bam!

q.