Metamodelling for Software Engineering

4.3 PROCESS AND MODELLING CONFLICTS

We saw, in Chapter 3, the various application areas in which metamodels have been used. In particular, we showed how metamodelling underpinned the development of UML, which offers notational support for work products, and SPEM, which offers notational support for process elements of a methodology but excludes concepts found in the UML for work product descriptions.

A methodology, as we saw in Chapter 1, requires much more than just a modelling language and much more than just a process. Consequently, in our striving for a methodology metamodel, neither a modelling language, such as UML, nor a process modelling language, such as SPEM, is adequate. We need to investigate some combination or integration of these two – some attempts at such integration have indeed been made [3; 16, pp. 300, 305]. Here we review the issues involved and propose some solutions.

Modelling and process concepts are related in a number of ways; for instance, specific work products are created during the execution of a specific work unit, such as a task prescribed by the process. Classes – instances of the UML element Class – are usually created during IdentifyClasses – an instance of the OPF work unit Task. Of course, for any full-scale integration of “product” and “process”, it is necessary that the chosen pair of modelling and process frameworks contain the same (or at least a compatible set of) concepts. An interesting dilemma only becomes apparent once these statements ...