UMLR — Rg. Realization and InterfaceRealization

not sure, but the way how Interfaces are supposed to be realizd throughout the spec may need some more Clarification in the spec. I might have missed some discussions on this topic, though. If this has already been clarified (haven’t found an issue in the issue sheet for the component section), please ignore my question.

The required/provided Interfaces of Components are derived. The derivation algorithm (p 235) makes use of Classifier.allRealizedInterfaces() and C.allUsedInterface(). I do not have any problems with allUsedInterface, but allRealizedInterfaces() or more concrete directlyRealizedInterfaces() is not very well chosen I think. directlyRealizedInterface() is based on Realizations between the Classifier and an Interface. Given this, any Interface that is referenced by ComponentRealization or Substitution is part of the realized Interfaces of that Classifier.

As a BehavioredClassifier, a Component should make use of InterfaceRealization solely. However, the provided Interfaces of a Component rely on the above mentioned concept, i.e., a Realization between a Classifier and Interface. Of course, using an InterfaceRealization instead would also do the job and calculate the provided Interface of that Component correctly. In case of Class and Component, it is just confusing why the algorithm to calculate the provided Interfaces is based on Realization, whereas BehavioredClassifier uses InterfaceRealizations. It could be even more confusing, in case only Realization relationships are used to establish the provided Interfaces, asking for BehavioredClassifier.interfaceRealization might return an empty list, since all Interfaces are realized via Realization.

This may cause other issues: A DataType could establish a Realization dependency to an Interface. Classifier.allRealizedInterfaces() would return that Interface. This holds true for all non-Class Classifier, in fact. Is this a desired situation?