Elemental Design Patterns : A Logical Inference System and Theorem Prover Support for Flexible Discovery of Design Patterns

Previous approaches to discovering design patterns in source code have suffered from a need to enumerate static descriptions of structural and behavioural relationships, resulting in a finite library of variations on pattern implementation. Our approach differs in that we do not seek to statically encode each pattern, and each variant, that we wish to find. Rather, we encode in a formal denotational semantics a small number of fundamental OO concepts ( elemental design patterns ), encode the rules by which these concepts are combined to form patterns( reliance operators ), and encode the structural/behavioral relationships among components of objects and classes ( rho-calculus). A logical inference system then is used to reveal large numbers of patterns and their variations from this small number of definitions. Our system finds patterns that were not explicitly defined, but instead are inferred dynamically during code analysis by a theorem prover, providing practical tool support for software construction, comprehension, maintenance, and refactoring.