A Radical Revision of UML’s Role Concept

Abstract

UML’s current definition of the role concept comes with many problems, not the least being that it is difficult to understand and communicate. This paper proposes a revised UML metamodel building on a much simpler role definition. Moreover, it replaces the rather unusual notions of association role and association end role as well as the rarely used association generalization with the more popular concept of overloading, thereby leading to a considerable reduction in the number of modelling concepts. Despite the rather radical nature of the proposed alterations, no changes in UML notation become necessary. However, a notable change in modelling style including in particular a clearer separation of structure and interaction diagrams are among the likely effects of the proposed revision.