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

Abstract

Abstract. 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.

Quality of Merge-Refactorings for Product Lines

“…Several existing approaches aim at building product lines out of legacy artifacts, e.g., [8]. These approaches mainly provide guidelines and methodologies for identifying features and their related implementation components rather than build tool-supported analysis mechanisms.…”

“…Numerous works provide guidelines and methodologies for building product line representations out of legacy systems, e.g., [14,8]. Most of such approaches, however, involve a manual review of code, design and documentation of the system aiming at identifying the set of product line features, as well as the set of components which implement these features.…”

Model-Driven Engineering for Software Product Lines

“…Batory [50] introduces propositional constraints defined between features. Ferber et al [51] defines a separate view to represent feature dependencies and interactions. Figure 2 from [52] provides a synthesis of the concepts used to capture variability and how they are graphically represented by the feature modeling languages described in this section.…”

Aspectual Separation of Feature Dependencies for Flexible Feature Composition

“…To add the feature History, the calculators must be extended with a GUI button for upward navigation. The aspect HistoryMoudle creates an UpButton instance (line 3) and adds it to the calculator GUI Panel (line 7), after the join point specified at the pointcut SomeExtensionPoint(p) (lines [5][6][7][8]. The UpButton instance calls the method upHistory() (line 11), which implements the functionality for navigating through previous expressions in the history list and passing a selected expression to the calculator parser (lines 17-18), when the corresponding GUI button is pressed.…”

“…Note that the Usage dependency [7], [8], which corresponds to Inform and Data Flow dependencies in [9], is the most common form of feature dependency. However, we are not interested in this dependency because Usage dependencies do not vary independent from their associated features.…”