[news.eclipse.tools.emf] Re: User data in validation

[Vasanth Velusamy <vasanthv16@xxxxxxxxx>]

Christian,

Comments inline.

Christian W. Damus wrote:
> Hi, Vasanth,
>
> No, currently there is no such facility.  I think in the EValidator API, the
> context map is geared towards utilities that are known to and provided by
> EMF, such as SubstitutionLabelProviders.  It can be assumed that
> constraints in an EValidator will know what to do with these
> general-purpose context objects, but not application-specific objects.

With respect to the EValidator API, I have modified the generated 
XXXValidator (? EValidator). (It might be argued that I should have 
created a new EValidator and registered it?) Now, when I call the 
validator, I pass in additional context information in the context map 
and my new constraints make use of the additional context information.

> The assumption in the ModelValidationService is that if constraints are so
> tightly coupled with an application that they need to exchange such context
> data, then they can provide their own communication channel separately from
> the validation framework.  I'm not sure that this is always practical. 

As for now, I have made my generated XXXResourceImpl adaptable and it 
provides additional context information (Resource is not IAdaptable, but 
I made my generated XXXResourceImpl to be IAdaptable. This is not very 
elegant but it helps solve my problem for now). Since constraints have 
access to the EObject being validated (hence the underlying Resource), I 
am able to get my additional context information from this).

> Certainly, we're open to proposals to enhance this part of the API.

I would think that IValidator could have some way to set additional 
context that becomes accessible to all constraints as part of 
IValidationContext itself.

Thanks,
Vasanth


> Cheers,
>
> Christian
>
>
> Vasanth Velusamy wrote:
>
> > When using the EMF Validation Framework (ModelValidationService along
> > with constraints), how do I provide user-defined context data to the
> > constraints? AbstractModelConstraint.validate() provides an
> > IValidationContext from which I am able to retrieve the target and other
> > details, but how can I provide user context data to the constraint? I
> > understand that IValidationContext.get/putCurrentConstraintData() is for
> > a different purpose.
> >
> > In the EValidator api, I see that Diagnostician.validate() gives the
> > option to add user data as a context map (Map<Object, Object> context).
> >
> > Is there something similar when using the EMF Validation Framework?
> >
> > Thanks,
> > Vasanth