Knowledge-Based Requirements Analysis for Ada Design Recovery: Design Entity Identification and Representation

Constructs: extend package classification so that a lifted view of an Ada system at a level that deals entirely with abstract constructs (ADTs, ADSs, tasks, libraries, monitors, generics) would be possible. Object Hierarchies: The next stage on recovery of abstract constructs would be discernment of class and object hierarchies. There is already a substantial literature on class and object recovery from Ada source code in particular [5, 10]. DIMENSIONS OF DESIGN This paper concentrates on the issue identified above as a central advance over existing Ada design recovery capabilities: the recovery of abstract constructs from Ada code, specifically including how they can be visualised; but with the primary focus on what universe of abstract design entities should be the target of the recovery process. The usual criteria have significances as follows: • completeness: as wide as possible classification should be achieved; classifications as “unknown” should be minimised; • consistency: classifications should be unambiguous; the abstract view of a system should avoid conceptual redundancies. Our approach to achieving a consistent and complete set of design entities is to formalise the conceivable design space through an (as far as possible) orthogonal set of binary characterisations of abstract constructs. By taking each characteristic as a dimension, a space is generated, so that the universe of abstract constructs that could conceivably recovered is found by associating each point in the space with an identifiable programming/language abstraction. Rather than work our way through a mass of intuitions, with mutual overlaps (inconsistencies) and conceptual gaps (incompletenesses), we instead deal with a number of dimensions that is of the order of the log. of the number of design entities. The characteristics we perceive as the basis are as follows. Each dimension is characterised in terms of contrasting values “A vs B”, the first-mentioned value A to be re-