UML Modeling Support for Early Reuse Decisions in Component-Based Development

Component-based development is the software industry’s latest answer to some long-standing problems in software development. Its aim is to make actual reuse of existing software units (components) a widespread reality. We argue that significant reuse decisions can occur in the early stages of system development. Using a theory of the modeling process, we show that choice of abstractions and notations is critical. We investigate the kinds of models that would support early reuse decisions. We show that easily composable, business-oriented abstractions about software behaviour and a functional mental model are necessary. Evaluation of the UML in these terms emphasizes its bias towards structural mental models and abstractions derived from the software domain. INTRODUCTION Component-based development (CBD) is the software industry’s latest answer to some long-standing problems in software development (Allen & Frost, 1998; Szyperski, 1998). Building on lessons learned from earlier software-engineering innovations, CBD focuses on the goal of actual reuse of software (rather than reusability, which is simply the potential for reuse). This is seen as the key to a number of desirable economic outcomes, such as rapid development, clarification of developer roles and amortization of software development costs. If components are thought of simply as units of software, it might be concluded that reuse is mainly a matter for the design and construction phases of development, but we argue