Really Automatic Scalable Object-Oriented Reengineering

Even when implemented in a purely procedural programming language, properly designed programs possess elements of good design that are expressible through object-oriented constructs and concepts. For example, placing structured types and the procedures operating on them together in the same module achieves a weak form of encapsulation that reduces inter-module coupling. This paper presents a novel technique, and a supporting tool AutoOO, that extracts such implicit design elements from C applications and uses them to build reengineered object-oriented programs. The technique is completely automatic: users only provide a source C program, and the tool produces an object-oriented application written in Eiffel with the same input/output behavior as the source. An extensive evaluation on 10 open-source programs (including the editor vim and the math library libgsl) demonstrates that our technique works on applications of significant size and builds reengineered programs exhibiting elements of good object-oriented design, such as low coupling and high cohesion of classes, and proper encapsulation. The reengineered programs also leverage advanced features such as inheritance, contracts, and exceptions to achieve a better usability and a clearer design. The tool AutoOO is freely available for download.