Variability Modeling

The aim of this chapter is to provide a comprehensive description of the notion of variability modeling in the context of software product line engineering and to give an overview of the techniques proposed for variability modeling. Since its first introduction in 1990, feature modeling [1] has been the most popular technique to model commonality and variability (C&V) of products of a product line. Commonalities and variabilities are modeled from the perspective of product features, “stakeholder visible characteristics of products” in a product line that are of stakeholders’ concern. For example, the fund transfer feature of a banking system may be of interest to customers, i.e., a service feature, but how the fund transfer happens may not be of interest to customers as long as it is done securely. However, it will be an important concern for the designer of the system and, when there are alternative ways, it is the responsibility of the designer to choose the right one for the target system. The original feature model, FODA [1], is a simple model with features that are organized using “consists of” and “generalization/specialization” relationships