Business rule extraction from legacy code

Business rules are operational rules that business organizations follow to perform various activities. Over time, business rules evolve and the software that implemented them are also changed. As the encompassing software becomes large and aged the business rules embedded are difficult to extract and understand. Furthermore, the encompassing software is changed without changing the corresponding documents, so the business organization often trusts the code more than any other documents. It is possible to use a generic tool to extract business rules, but this can be an expensive exercise. The paper proposes a tailored solution approach to the business rule extraction problem, which combines variable classifications, program slicing, and hierarchical abstraction among other maintenance techniques. The proposed approach has been implemented as a system and successfully experimented with a number of industrial programs. The prototype has been demonstrated at several industrial software maintenance sites since June 1995.