A survey of representations employed in object-orientated programming

This document presents an overview of the program visualisations additional to the program code provided by some of the most popular object-oriented programming environments to support tasks involving program comprehension. These representations were compared in terms of the programming aspects they highlight and of their information modality. Those with common characteristics according to these criteria were identified. Finally, a brief analysis of these common representations in terms of Green's Cognitive Dimensions is presented. Two questions arising from this survey are (a) whether representations additional to the code should be redundant and highlight similar information to the main notation or be complementary and highlight different programming aspects and (b) which factors might increase the cognitive difficulty of co-ordinating these additional representations and the program code. More theoretical knowledge about the way these additional representations influence the comprehension of computer programs seems to be needed.