RE2: Reverse-engineering and reuse re-engineering

Initial research in reuse was in the designing and implementation of reusable software. This research, although fruitful, did not address the area of extracting reusable components from existing software. In this paper the term reuse is used to mean the ‘reuse of existing source code’. A process called ‘reuse re-engineering’ is defined and this, together with techniques from reverse-engineering, form a new method for achieving reuse. A reference paradigm is established to implement the reuse re-engineering process. This process is divided into five sequential phases, each characterized by the objects it produces. These phases are: candidature, election, qualification, classification and storage, and search and display. This paper concentrates on the first three phases because they produce reusable modules from existing systems. In selecting candidates for reuse, different abstractions have to be applied, namely functional abstraction (algorithms) and data abstractions (data structures and data types). This paper presents a formalized approach to each of these abstractions. The approach proposed in this paper aims to promote reuse in industrial software production environments.