Stability of Product Lines with Composition Filters: An Exploratory Study

With system development becoming increasingly incremental, design stability stands out as one of the most desirable software quality attributes. Development of stable software systems is particularly challenging in the domain of software product lines (SPLs), where their core architecture, set of features, and multiple products are continuously evolving. Contemporary programming languages, such as Compose*, are promising solutions to support enhanced SPL stability through the notion of composition filters. Aspect-oriented and feature-oriented programming models have often being used and assessed in the context of SPL development. However, there is little empirical knowledge on which situations such composition filters mechanisms, in fact, can be used to build SPLs with superior stability. This paper presents an exploratory study that compares the stability of Compose* and AspectJ implementations through multiple releases of two product lines. These implementations are evaluated by means of independentlyvalidated stability metrics. Our results show that the use of Compose* to implement non-functional features and interacting code-sharing features often foster more stable SPL designs than AspectJ ones.