Re: [mdr-users] createExtent(String, RefObject, RefPackage[])

Hi Martin,

On 8/5/05, Martin Matula <[email protected]> wrote:
> Pieter Van Gorp wrote:
> >Hi all,
> >I'm looking for some information on the method to create an extent
> >that clusters an already existing extent:
> >(i.e. http://www.netbeans.org/download/dev/javadoc/MdrAPIs/org/netbeans/api/mdr/MDRepository.html#createExtent(java.lang.String,%20javax.jmi.reflect.RefObject,%20javax.jmi.reflect.RefPackage[])
> >)
> >
> >A short explanation of the array argument or some example code should do it.
> >
> >I passed a one-size array containing a UML extent to it but the
> >clustered UML extent of my tracing extent (see
> >http://www.fots.ua.ac.be/motmot/docs/traceability-p3.php) remains
> >empty.
> >
> That's weird - it should work correctly. I.e. if package A clusters
> package B and you create instance of B, then if you pass this instance B
> into the createExtent() method to create extend A, the instance of B
> should be reused.
Well, this is not the case in my test: a call to
handleToTraceModel.getUml().getCore().getAttribute().refAllOfClass().size()
returns 0 while the original UML model contained a lot of attributes. 
My other mail also indicates the UML sub-extent is empty... I'll
prepare a small test to reproduce this with minimal effort.

> >I already found it a bit weird that I didn't have to specify
> >in which package of the tracing extent the existing UML extent should
> >be loaded.  Sure, in my case there's only one clustered UML extent but
> >problems should arise as soon as there would be more... therefore I
> >must be missing something...
> >
> >
> This is not weird. According to MOF semantics, if A and B both cluster
> C, then only one instance of C is created and shared by both A and B.
> Similarly, if an instance of C already exists and you are creating
> instance of A and B (or D which owns A and B), then the instance of C is
> reused for both.
I was thinking of the situation of clustering the same metamodel twice
but I guess MOF does not allow to do that because it would require
importing the same package twice?

Regards,
-- Pieter.