Tuesday, July 31, 2007

No more NPE when generating models

For most users, EMF 2.3 is all about Java 5.0. Although most of our time was certainly spent on Generics and other "5isms", we sure managed to implement a few nice features as listed in our release notes. BTW, I know that this report is not as beautiful as a "New and Noteworthy" page, but that's the best we can offer now. Note to Wassim: I promise we will try to improve for this release ;-)

Of these nice features, the one I think I like the most is the complete validation of Ecore models. Basically this work consisted on defining and implementing all the constraints that characterize a well-formed model using the EMF Validation framework. Without an automated way to check these constraints, aka "before 2.3", any poor soul manipulating Ecore models would probably end up getting all sorts of exceptions when generating the code for the models. In face of these exceptions, the users would do the simplest thing available at the time: post a question on the newsgroup and wait the excruciating 10 minutes delay that usually takes Ed to answer.

Now this has changed! To check if your model is correct, hence capable of being used for code generation, all you need to do is to either open the .genmodel file editor or, on the .ecore file editor, select a package and run the Validation action available in the context popup-menu. Any existing problem in your model will be then presented in a tree viewer, with (hopefully ;-) all the information you need to have it fixed.

I should mention that EMF 2.3 can validate any Ecore model. So even if you are using an older version of EMF and usually edit your Ecore models directly, I believe the model validation justifies having the 2.3 release installed somewhere in your machine.

1 comment:

Nick said...

For more EMF 2.3 New and Noteworthy, see the wiki. Coming next year, we might get fancy and try to do generated N&N. But Wassim will probably complain anyway. ;-)