Composing Design Models: An Extension to the UML

Abstract

A structural mismatch between the specification of requirements for software systems and the specification of object-oriented software systems happens because the units of interest during the requirements phase (for example, feature, function etc.) are different from the units of interest during the object-oriented design and implementation (for example, object, class, method etc.). The structural mismatch results in support for a single requirement being scattered across the design units and a single design unit supporting multiple requirements — this in turn results in reduced comprehensibility, traceability and reuse of design models. Subject-oriented design is a new approach to designing systems based on the object-oriented model, but extending this model by adding new decomposition capabilities. The new decomposition capabilities support a way of directly aligning design models with requirements. Composition of design models is specified with composition relationships. This paper describes changes required to the UML metamodel to support composition relationships.

This work was performed while the author was at Dublin City University