QuickLink and Instances

[Paolo F Cantoni]

In the MDG we're creating, we make a significant use of instances (that is, we create instance models).

For example, we use Actor Instances, Artifact Instances, Objects etc.

We've started to set up a Quick Linker to allow us to create specific relationships between specific element types.  However, When we get to instances we seem to come to a screeching halt.  On the list of elements when you drag a Metaclass onto the Profile, there is an entry for Object but NOT for any other type of Instance.

Does anybody know how to create a Metaclass for an Actor Instance for example?

TIA,
Paolo

[Paolo F Cantoni]

Bump!

Sounds like Feature Request Time...

Paolo

[Paolo F Cantoni]

Bump!

Sounds like Feature Request Time...

Paolo

Requested,

Paolo

[«Midnight»]

I suppose I should have been more inclusive in my reply elsewhere. Instances seem relegated to obscurity in EA. This affects how they may be used, severely constraining some uses of UML within EA.

Thanks for making the requests.

[Paolo F Cantoni]

I suppose I should have been more inclusive in my reply elsewhere. Instances seem relegated to obscurity in EA. This affects how they may be used, severely constraining some uses of UML within EA.

Thanks for making the requests.

I've received a reply from Sparx indicating they are researching the issue.

However in the light of recent discussions in the forum on the subject of Instances, I responded with:
You might want to check out:
Action as Activity instance?

IF EA were to take the view that Objects (Instances) took their type from the classifier, then you might be able to get away with adding a new column on the end of the QuickLink CSV that said something like "Select Classifier for Instances".  Which would prompt using the Select Classifier dialog either before or after creating the Object (specified as the new element type)
Thoughts? Votes?
Paolo

[AlexY]

Does anybody know how to create a Metaclass for an Actor Instance for example?

It is important to remind the UML architecture consisting from:
(meta-meta model)
(meta model)
(model)
(runtime model)
Paolo,
A Metaclass for an Actor instance(runtime level) is an instance (model) of classifier Actor (meta model).
Example:
Actor (metamodel)
Customer:Actor (model)
Bob:Customer (runtime)

Do you see this differently?


So, an instance specification is its corresponding classifier is on different levels with “meta” type relationships between them. I do not recall such relationship defined in UML actually, but it is obviously the case here. Such “meta” type relationship is a mandatory element for instance specification to have sense.
So the bottom line.. I do not see a point to have an instance specification of unknown classifier and as such I support the recommendation to show “instance classifier” dialog when an instance specification is created. If existence of the meta type relationship is not enforced, at least there should be a way to assign such relationship in a more efficient way. So the recommendation gets my vote.


Another thought about the EA and instances. Relationships defined between classifiers (model level) are not enforced in models of instances of these classifiers. If this is indeed the current EA state (and I am not missing some option in the deeps of EA), then I believe it is time to request such a feature as often it is vitally important to enforce consistency across the 2 meta levels of the models.
What do you think?

[Geert Bellekens]

Another thought about the EA and instances. Relationships defined between classifiers (model level) are not enforced in models of instances of these classifiers. If this is indeed the current EA state (and I am not missing some option in the deeps of EA), then I believe it is time to request such a feature as often it is vitally important to enforce consistency across the 2 meta levels of the models.
What do you think?

I would love a way to instantiate relations defined between classifiers to create links between instances of these classifiers.
That is indeed a missing feature in EA.

Geert

[Paolo F Cantoni]

Received from Sparx:
We could possibly implement this in the way you described below.  I have submitted a feature request so that this is considered for implementation in a future release.  If you have any other information or suggests on how this could be implemented please let us know.
So it looks to me that we users should help with whatever ideas it would make sense to implement in this space.  As <Midnight> lamented Instances have been a somewhat ignored area of EA.  IN the kind of modelling I'm doing at the moment, I'm using a lot of them in interesting ways and I'm coming up against the current limitations.

Paolo