Feature oriented-programming

Abstract

Feature-oriented programming has its origin in the old quest of computer science: modular composition of software "artifacts" in software development. While there exist many notions of modularity and composition, feature-oriented programming tackles the case of highly-entangled software features where typical module or component concepts fail. The reasons for this are feature interactions and dependencies which make it very hard to write modular software which can be composed in a flexible way. In contrast to other efforts like aspect-oriented programming, feature-oriented programming has from the beginning focused on the semantics or behavior of software, not just on code modularity. In this presentation, we review the origins of feature composition and feature interactions, which first occurred as an explicit research problem in telecommunication software. We argue that feature interactions are pervasive in many areas of software development and are a common source of modularity and quality problems. Then, we present more precise formalization of modularity and compositionality of features. We discuss when adding features is modular or "harmless" from a semantic or behavioral point of view. In particular, we focus on modularity and interaction for multiple feature compositions. A future challenge for feature-oriented software is the graphical modeling of features and feature interactions. As we aimto have modular composition for graphical models and to generate code from these graphical artifacts, it is important to have precise semantics and clear refinement concepts. For this, we discuss how features and interactions can be represented by state-based specifications in a graphical way. Refinement concepts are presented which allow the flexible composition of features and interactions in statechart diagrams.