Detecting and Describing Variability-Aware Design Patterns in Feature-Oriented Software Product Lines

Software Product Lines (SPLs) enable customization by reusing commonalities and variabilities within a family of similar software systems. Design patterns are best practices of established solutions in object-oriented source code for recurring design challenges. Although certain design patterns realize variability, they are only defined in the context of stand-alone systems and not for SPLs. Employing design patterns to realize variability allows using best practices in design for SPL development. However, the exact usage of design patterns within SPLs has not been explored, and a formal notation to capture their usage within different features does not exist. In this work, we provide a model-based analysis method to determine the variability-aware usage of design patterns in source code within the context of Feature-Oriented Programming (FOP). Moreover, we introduce Family Role Models (FRMs) as an extension to role modeling, which offer a language-independent, unified, formal notation for decomposed design patterns. We apply the analysis method in a case study on the variability-aware usage of design patterns in feature-oriented SPLs and derive FRMs from the results.