Abstract

This study analyzes object-oriented (OO) program comprehension by experts and novices. We examine the effect of expertise in three dimensions of comprehension strategies: the scope of the comprehension, the top-down versus bottom-up direction of the processes, and the guidance of the comprehension activity. Overall, subjects were similar in the scope of their comprehension, although the experts tended to consult more files. We found strong evidence of top-down, inference-driven behaviors, as well as multiple guidance in expert comprehension. We also found evidence of execution-based guidance and less use of top-down processes in novice comprehension. Guidance by inheritance and composition relationships in the OO program was not dominant, but nevertheless played a substantial role in expert program comprehension. However, these static relationships more closely tied to the OO nature of the program were exploited poorly by novices. To conclude, these results are discussed with respect to the literature on procedural program comprehension.