[news.eclipse.tools.emf] [Fwd: Re: Non-containment for a child reference

[Christophe Bouhier <dzonekl@xxxxxxxxx>]

Hi Alex, (CC emf group, as this is also an EMF question).


I have played around with your suggestion, see inline experience below.


Maybe the deeper question is, how do I create a semantic model of nested
elements (Of the same type) which form a tree structure. The tree
elements need to be re-usable (So if contained they woudn't be reusable,
and need to be therefor non-contained references which causes the
problem described earlier).

E<--E<--E
    ^
    |
    E<--E
        ^
	|
	E


<-- is non-containment reference.


This model, has to be gmf friendly so to say and allow the nested tree
to be visualized in compartments.

It seems to me, that this problem is a generic pattern others must have
run into. When modeling a system (i.e. a computer), it has parts which
has subparts etc.. forming the tree structure. Of course a part could be
used in another computer product. When I use a containment feature , it
can't be used in multiple computers. (In EMF, the part would be moved
around). I could make a copy of the part, but this means a lot of
duplication.

What's the solution for this?


many thanks Christophe


Alex Shatalin wrote:
> Hello Christophe,
>
> Youcan ignore warning, generate code and corect generated code to 
> get/assign child element to the appropriate parent one.

Ok, when ignoring the warning, the gmfgen gets produced, the code breaks
in one code file:

1: xxxDiagramUpdater.java

getElementElementCompartment_7001SemanticChildren(...)

This makes sense, the semantic children for element are not contained in
this domain element but "somewhere else", I could change this to
"somewhere else".

Note: I realize it's not a very good idea to name elements "Element" in
the semantic model :-)


> Anoter option is to create derived feature in parent domain model 
> element, implement it in EMF so it will assign child element to the 
> appropriate container and use this feature as a containment one (.gmfmap 
> editor does not allo it, but you can do that by changing text file).

Need to dive into this, not sure how a derived feature can be created
with an .xsd meta model, or do I adapt the feature in .ecore?

> -----------------
> Alex Shatalin