Integrating Feature Modeling into UML

Feature modeling is an important approach to dealing with variability at an abstract level in a hierarchical manner extensively used in software product lines. For its use in conjunction with other UML models and MDA approach, it is important to correctly integrate feature modeling into UML. In this paper, we present an approach to integrating feature modeling into UML that respects abstractness of feature modeling elements. This is achieved by deriving feature modeling elements from the deeper levels of the UML metamodel. We applied this approach to the essential elements of feature modeling in the cardinality-based Czarnecki-Eisenecker notation and selected elements specific to other notations. Since UML modeling tools do not support such modifications of the UML metatmodel, in order to facilitate experimentation with combining elements from different notations, we implemented this feature modeling extension as a UML profile (in Enterprise Architect and Omondo UML).