Tracing imperfectly modular variability in software product line implementation

Abstract

When large software product lines are engineered, a combined set of traditional techniques, e.g., inheritance, design patterns, generic types, is likely to be used for realizing the variability at the implementation level. In these techniques the concept of feature, as a reusable unit, does not have a first-class representation in implementation, but still an imperfect form of modularization of variability can be achieved. We present in this paper a framework (i) to explicitly capture and document this imperfectly modular variability – by several combined techniques – in a dedicated variability model, and (ii) to establish trace links between this model and the variability model at the specification level. We report on the implementation of the framework through a domain specific language, and show the feasibility of the approach on a real feature-rich system.