A layered approach to automatic code generation and testing based on design units

The challenge faced by software developers is how to capture dynamically changing requirements and how to maintain consistency between the graphical models and the code generated to support the evolution of complex software. The use case driven approach has become extremely popular as an effective software development technique used in leading methodologies such as Unified Modeling Language (UML) because of its capacity for capturing functional requirements. However, use case driven methodologies do not sufficiently provide the systematic development process supported by a manageable relationship between design and the actual implementation. We propose an integrated, traceable software development approach in the context of a use case design methodology that achieves several quality control properties. As part of this approach, a layered architecture and a code generation model are introduced. The foundation of our approach lies in partitioning the design schemata into a layered architecture of functional components called design units. Design units provide the basis for the generation of modular, well-structured source code, the traceability of requirements throughout the software development process, the integration of test stubs into a structured code environment and the framework for a systematic approach to change management. We also developed a conversion algorithm that converts high-level design elements into code skeleton. Our skeletal code is generated from the interaction diagrams and event state tables in which the design units have been identified. In addition, we propose a complex interaction diagram and extended event state table in order to describe various associations between use cases.