Maybe I can ask for somebody to enlighten me please on the various "formats" of representing UML models (and their respective file extensions - accommodating all those PC guys who seem to insist on representing the format and content of a file through the, rather arbitrary, choice of file name extension).
First, we have UML models in two shapes: UML 1.x and UML 2.x. And, the second parameter is the representation of such a model in XMI (again, v1.x and v2.x).
Now, my experience has been that typically a UML 1.x model will be exported to a shape of XMI 1.x - with a file extension of .xmi or, possibly, .xml.
With the advent of UML 2.x (aka UML2), I seem to find that, analogous to the above, we export to XMI 2.x - again, with file extension of .xmi.
BUT, as Simon pointed out above, each model is expressed with respect to a meta-model. And there appear to be differences in these meta-models (as there reasonably would be - although I don't see why that effects the shape and form of the actual model in XMI as it comprises presumably standardized UML constructs). And so here we have it: the Eclipse EMF seemingly expects models to be expressed w.r.t. to the EMF/Ecore meta-model - and, thus, we have EMF/XMI. If this is correct, however, it begs the question as to what EA's meta-model is when exporting to XMI2? It's own... EA meta-model?
Am I correct in all of this? Please comment...
And, where does the file extension .uml2 fit in? Well, no idea... Somebody, please enlighten me ;-)
And, Birgit, BTW, unless you're using AndroMDA v4, EA exports of models into UML1/XMI1 work just fine. I have been using EA in conjunction with AndroMDA v3.x for some time now with very good success.
ciao,
-olaf