Thoughts on add-in to visually compare models

[MattAdamson]

I was thinking of developing an addin to allow visual comparison of two models and would like your thoughts.

The tool was going to be used in conjuction with the standard compare utility to allow more detailed and structured differencing however I'd like the visual diagram differencing to focus on key things we notice change with design revisions namely

1) New elements
2) Elements removed
3) New / removed / changed attributes and operations to elements.
4) New / removed connections between classes

You can easily obtain the differences between two packages as an XML file. I was going to parse the XML file to extract the specific differences and then draw all the elements in the diagram and colour different elements / attributes / operations / connectors to indicate whether there were new / removed or changed.
If the notes had also changed for any of these types of elements it would also be indicated with a different colour.

As the automation model doesn't show elements which have been removed and also provides no support for colouring specific operations / attributes you can't use the EA object model to draw a new diagram. The only approach I was thinking of was drawing on a .NET user control embedded within a new tab created with AddTab

I thought this would be really useful for design reviews when most of the time changes focus on specific diagrams where it is useful to see the changes without having the traverse through the tree hierarchy of the compare utility.

Thoughts?

[Paolo F Cantoni]

We'd Beta Test it...  

Paolo

[MattAdamson]

Thanks however I'd appreciate it if anyone has thoughts in relation to features they'd like to see.

Also do any other UML products provide this feature. I couldn't see this in Rational Rose Enterprise or Visual UML, surely someone has written one?

[barny451]

Both Telelogic UML tools Tau and Rhapsody have full model visual compare and merge.  Tau has 3- and 4-way merge.

HTH
Barny

[MattAdamson]

Sorry should have clarified that I meant visual compare in terms of the diagrams.

I downloaded Rhapsody and couldn't see any feature to compare two UML diagrams indicating the changes on the actual diagram e.g. new operations highlighted in a certain colour

[Weedman]

What about comparing two activity diagrams?

Would all the tabbed fields for properties of elements being compared be checked for differences?

Regards,
Weedman

[barny451]

Sorry for not replying earlier, been on holiday  

In Rhapsody 7.0 (and in earlier versions I believe), there's a DiffMerge entry in the Rhapsody installation, i.e. under Start->All Programs->Rhapsody 7.0->DiffMerge.

This does 2-way or base-aware (3-way) compare/merge of the model and of the diagrams.  You can set it to ignore layout differences, e.g. where a symbol has been moved.

Comparing the model means showing all added/deleted/changed things, whether elements, connectors, issues, risks, requirements, etc., and attributes of all these things.

Looks like a complicated project you're taking on  

HTH
Barny

[mark.myers]

Did this end up going anywhere?
I would like to be able to do visual comparision of differences, ie a diagram before and after changes.

[thomaskilian]

Maybe you should not expect more functionality for less price. It would surely be nice to have these features, but they definitely would mean a large increase not only in price for EA but also for possible bugs and more EAUI. Thus I would not opt for such a feature. Except, maybe, it would be available as separate package with an extra price

[bmioch]

I know this isn't an exact solution to this problem, but it may be suitable for some people.

If you have Auditing on, you can set a custom time period, switch to Standard Mode and click on the diagram in the Tree Browser. That should list all changes to the diagram (and it's contents) for that period, which is kind of like a compare.

Under Audit Settings, if Standard level is selected, moving objects on a diagram won't be recorded. If Extended level is selected, they will.

[mark.myers]

Thanks for the replies - good thoughts. I am putting together a quick and dirty addin that will just show the diagram image as it is now side by side with a previously saved version. I think this will keep the client happy.