An Interactive Viewpoint on the Role of UML

Abstract

The role of the Unified Modeling Language (UML) is to model interactive systems, whose behaviors emerge from the interaction of their components with each other and with the environment. Unlike traditional (algorithmic) computation, interactive computation involves infinite and dynamic (late binding) input/output streams. Tools and models limited to an algorithmic paradigm do not suffice to express and manage the behavior of today’s interactive systems, which are capable of self-reconfiguring and adapting to their environment. Whereas procedural languages may express precise designs of closed processes, UML’s objective is to provide support for the analysis and specification of increasingly complex and inherently open systems. Interactive systems require dynamic models where interaction has first-class status, and where the environment is modeled explicitly, as a set of actors whose roles constrain the input patterns through use cases. UML’s interaction-based approach to system modeling fits well with the encapsulation-based, object-oriented approach to implementation. By coupling these approaches, the software engineering process can promise to provide a more complete solution to system design and implementation, leading the way for widespread adoption of networked and embedded intelligent agent technology. A theoretical framework for modeling interactive computing can strengthen the foundations of UML and guide its evolution.