Déjà Vu: A Hierarchical Case-Based Reasoning System for Software Design

Déjà Vu is a case-based reasoning system for software design. This paper describes the hierarchical case-base in Déjà Vu and the blackboard based architecture that controls reasoning with this case-base. The case-base is structured as a partonomic hierarchy. Each complete solution in the case base is represented by a top-level case describing the outline of the solution. This top-level case contains pointers to several 'detail cases' representing the modules that make up the solution. In addition the case base has a taxonomic structure that facilitates case retrieval. The partonomic structure of the case base requires that the case base reasoning process is multi-stage rather than the singlepass retrieval process that is normal in case-base reasoning. In Déjà Vu a solution is built by first retrieving and adapting a top-level case and then retrieving and adapting detail cases to build up this solution. The control issues introduced by this multi-stage case-base reasoning is addressed by organising the system as a blackboard system with dedicated control agents organising the reasoning process. Published in Proceedings of 10th European Conference on Artificial Intelligence, 1992, Vienna, Austria.