Viewpoints and Objects

There have been a number of proposals to split the specification of large and complex systems into a number of inter-related specifications, called viewpoints. Such a model of multiple viewpoints forms the cornerstone of the Open Distributed Processing (ODP) standardisation initiative. We address two of the technical problems concerning the use of formal techniques within multiple viewpoint models: these are unification and consistency checking. We discuss the software engineering implications of using viewpoints, and show that object encapsulation provides the necessary support for such a model. We then consider how this might be supported by using object oriented variants of Z.