A Layered Software Specification Architecture

Separation of concerns is a determining factor of the quality of object-oriented software development. Done well, it can provide substantial benefits such as additive rather than invasive change and improved adaptability, customizability, and reuse. In this paper we propose a software architecture that integrates concepts from business process modeling with concepts of object-oriented systems development. The presented architecture is a layered one: the concepts are arranged in successive layers in such a way that each layer only uses concepts of its own layer or of layers below. The guiding principle in the design of this layered architecture is the separation of concerns. On the one hand workflow aspects are separated from functional support for tasks and on the other hand domain modeling concepts are separated from information system support. The concept of events (workflow events, information system events and business events) is used as bridging concept between the different layers.