Software reengineering for complex systems

Reengineering complex software is a difficult task that requires the expenditure of significant resources. To reduce associated costs and improve resultant systems, automated techniques have been developed that can be used throughout all phases of the reengineering process. Three systems are described that have been used successfully for reengineering at The Johns Hopkins University Applied Physics Laboratory. The first system automatically transforms software written in CMS-2 to software written in Ada. The second system supports database design and automated query formulation, and employs conceptual-level intermediate representations for reverse and forward engineering as well as reengineering. The final system utilizes automated techniques to reengineer critical functions for performance enhancement. The systems described are evolving, and will provide a basis for future reengineering efforts.