From Patterns to Components: The Factory Library Example

Can design patterns be turned into reusable components using some advanced programming language mechanisms? We reviewed all patterns described in the book by Gamma et al. [Gamma 1995] and built a new classification of these patterns by level of “componentizability” (possibility to turn the pattern into a component). This article first describes our “componentization” approach and the pattern classification we obtained [Arnout 2004b]. Then, it focuses on one “componentizable” pattern, Abstract Factory, and explains how we devised the corresponding Factory Library in Eiffel. Finally, it describes the limitations of the approach and presents related works, before giving some future research directions.