[news.eclipse.tools.emf] Re: Attribute dependency validation

[Ed Merks <merks@xxxxxxxxxx>]

José,

Comments below.

José Parera wrote:
> I have a problem when I try to validate an attribute that depends on 
> another.
> Let's suppose I have a XSD model in which attribute A of type double 
> has a valid range of values that depends on the value of another 
> attribute B, also double. Let's say that the range of values of A is 
> 0.5*value(B) ... 1.5*value(B). I need a 'live' validation of the 
> attribute as is done on the generated editor.
>
> The generated Validator simply checks the range of A against fixed 
> values specified using minInclusive and maxInclusive. I wish to modify 
> the generated validateA (or validateA_Min/Max) method to take account 
> of the dependency. The trouble is that I don't know how to access the 
> EObject instance being validated  because the methods are called with 
> just a double parameter. I thought that the context parameter will be 
> useful but I couldn't get the instance reference from it.
The facet constraints are directly constraints on a data type's value 
and are independent of where those might be used.  You really would want 
to define a constraint on the complex type itself to define a constraint 
between the attributes within that complex type.  You could do that with 
an ecore:constraints annotation on the complex type and would just name 
the constraints, e.g., ecore:constraints="AProperlyRelatedToB".  This 
will generate a hook in the XyzValidator and you can specialize that to 
implement the logic for the constraint.
> Are there any simple trick to do such a validation?
>
> Thanks in advance