Designing application domain models with roles

This article is motivated by two related observations. First, roles, responsibilities and collaborators are central to object interactions, and viewing of objects from these three dimensions can yield a more dynamic and flexible design than that from the class dimension. Yet the orthodox object modeling approaches, such as UML, still adopt the class view of objects. Second, models have become increasingly important in constructing application systems. For example, OMG's Model Driven Architecture (MDA) uses models as building blocks to support application development. Based on the assumption that object-oriented approaches will still dominate the development of the MDA models, this article posits that the new models be oriented towards the roles, not towards the classes; it shows why roles are importance to MDA model design. © Springer-Verlag Berlin Heidelberg 2005.