Injecting quality attributes into software architectures with the common variability language

Quality attributes that add new behavior to the functional software architecture are known as functional quality attributes (FQAs). These FQAs are applied to pieces of software from small components to entire systems, usually crosscutting some of them. Due to this crosscutting nature, modeling them separately from the base application has many advantages (e.g. reusability, less coupled architectures). However, different applications may require different configurations of an FQA (e.g. different levels of security), so we need a language that: (i) easily expresses the variability of the FQAs at the architectural level; and that (ii) also facilitates the automatic generation of architectural configurations with custom-made FQAs. In this sense, the Common Variability Language (CVL) is extremely suited for use at the architectural level, not requiring the use of a particular architectural language to model base functional requirements. In this paper we propose a method based on CVL to: (i) model separately and generate FQAs customized to the application requirements; (ii) automatically inject customized FQA components into the architecture of the applications. We quantitatively evaluate our approach and discuss its benefits with a case study.