Object- Orient ed Design by Transformat ions

This paper discusses the nature of object-oriented design within the classic software engineering framework of Analysis, Design, and Implementation phases. In our model, Design is decomposed into three distinct ordered activities, each addressing a specific aspect formulated by the specifications: functionality, resource constraints, and performance requirements. Decoupling these design activities should enhance the micromanagement of the software development process. Such decoupling can be ultimately embedded in CASE tools to guide designers. A by-product of such decomposition is a disciplined method for the construction of early prototypes.