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Tue, 22 February 2011 07:02

Eclipse User

Hello every experts ,

I am writing a program in Java,using Eclipse for providing the user by the ability to apply some operators on a per developed UML Model of any software. one of this operators is to add a new Operation into an interface , so that all the related elements that interface has to be updated.

I need to use the @pre in the post conditions as you see in the following short code.:

String test="Dependency.allInstances()->select(getAppliedStereotypes().name- > includes('AddPhenomenon')).source.oclAsType(Interface).owned Member.oclAsType(Operation)- > forAll(op:Operation|Operation.allInstances()->select(name=op.name)- >size()=1)";

Constraint consTest=(Constraint)oclHelper.createInvariant(test); existsDepndency_AddPheno=ocl2.check(this.model, consTest);

if(existsDepndency_AddPheno)

The result is that : the @pre is to be used in the method post conditions, so how can I use it. where exactly I could embed the code of post conditions in the Java program?

Re: using @pre. operator. [message #655743 is a reply to message #655710]

Tue, 22 February 2011 09:37

Eclipse User

Hi Hussam,

you should be able to use @pre as a postfix to the property you're trying to access in a postcondition. The parser will then mark the expression correspondingly internally.

Evaluation time is a different question. I don't know how the values prior to a single change or a whole set of changes are preserved for OCL evaluation. The evaluator code doesn't make reference to isMarkedPre() on PropertyCallExp, so I would assume it doesn't have an impact on evaluation. Maybe Ed Willink is able to answer this. Ed?

As an additional hint, although I understand you're using the UML implementation of MDT/OCL and not the Ecore implementation, maybe have a look at PartialEvaluator and PartialEvaluatorFactory. For the Ecore flavor of MDT/OCL it can take an EMF change Notification and compute an expression based on the state of the model *before* the change happened.

Best regards,
-- Axel

Re: using @pre. operator. [message #655749 is a reply to message #655743]

Tue, 22 February 2011 09:47

Eclipse User

Hi Axel,

I really did mistake in the example code in this topic, but I did create a new topic with the correct example, and the correct error message from the ocl parser.

I am using Eclips, in Plugin perspective, and UML model in Papyrus.

best regards,

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