Abstract

Software design is a difficult creative task learnt from long experience. Reusable object-oriented design aims to describe and classify designs and design fragments so that designers may learn from other peoples' experience. Thus, it provides leverage for the design process. The evolution of a B-tree indexing system, which is a component in a database management system, is presented to illustrate how design patterns clarify the design and make it more understandable. This re-engineering is a necessary step towards a reusable design and implementation for multi-dimensional indexes. It also demonstrates the reuse of the design knowledge captured in design patterns.