Expert maintainers' strategies and needs when understanding software: a case study approach

Accelerating the learning curve of software maintainers working on systems with which they have little familiarity motivated this study. A working hypothesis was that automated methods are needed to provide a fast, rough grasp of a system, to enable practitioners not familiar with it, to commence maintenance with a level of confidence as if they had this familiarity. Expert maintainers were interviewed regarding their strategies and information needs to test this hypothesis. The overriding message is their need for a "starting point" when analysing code. They also need standardised, reliable and communicable information about a system as an equivalent to knowledge available only to developers or experienced maintainers. These needs are addressed by the proposed "roughcut" approach to program comprehension. Work underway assesses the suitability of using data mining techniques on data derived from source code to provide high level models of a system and module interrelationships.