Feature Interaction and Dependencies: Modeling Features for Reengineering a Legacy Product Line

Reengineering a legacy product line has been addressed very little by current product line research activities. This paper introduces a method to investigate feature dependencies and interactions, which restricts the variants that can be derived from the legacy product line assets. Reorganizing the product line assets with respect to new requirements requires more knowledge than what is easily provided by the classical feature-modeling approaches. Hence, adding all the feature dependencies and interactions into the feature tree results in unreadable and unmanageable feature models that fail to achieve their original goals. We therefore propose two complementary views to represent the feature model. One view shows the hierarchical refinement of features similar to common featuremodeling approaches in a feature tree. The second view describes what kind of dependencies and interactions there are between various features. We show two examples of feature dependencies and interactions in the context of an engine-control software product line, and we demonstrate how our approach helps to define correct product configurations from product line variants.