Managing Software Architectural Evolution at Multiple Levels of Abstraction

Software development is a dynamic process where engineers constantly modify and refine systems. As a consequence, system architecture evolves over time. Software architectural evolution has been managed at different abstraction levels: the meta level, the architectural level, the application level, and the implementation level. However, management supports for architectural evolution are limited to evolution mechanisms in architectural description languages such as subtyping, inheritance, interface, and genericity. This paper presents a model-oriented version and configuration control approach to managing the evolution of architectural entities and relationships among them in configurations at different levels of abstraction. This paper also illustrates our approach in building an architectural configuration management system,MolhadoArch, that is capable of managing configurations and versions of software architecture across multiple levels of abstraction in a uniform and tightly connected manner. In MolhadoArch, consistent configurations are maintained not only among source code but also with the high-level software architecture. MolhadoArch supports the management of both planned and unplanned evolution of software architecture. We have conducted an experimental study to show that MolhadoArch can handle large and real-world systems. By evaluation, we learned that the benefits outweigh the extra space needed to represent architectural entities.