Supporting Aspects in Mda

For developing large and complex applications, industrial practice uses a combination of nonformal notations and methods. Different notations are used to specify the properties of different aspects of an application and these specifications are transformed into their corresponding implementations through the steps of a development process. The development process relies heavily on manual verification to ensure the different pieces integrate into a consistent whole. This is an expensive and error prone process. Model-driven development approach addresses this problem by providing a set of modeling notations for specifying the different layers of a software architecture and a set of code generators for transforming the models into an implementation. Model-driven development has resulted in improved productivity, better quality and platform independence. However, it has not been very successful in supporting reuse and system evolution due to inadequate modeling support for clear separation of concerns and their composition. The model driven architecture (MDA) initiative of OMG aims to shift the focus of software development further towards modeling. With model content in system specifications increasing more and more, it is critical to address the issue of separation of concerns at model level. Aspect oriented programming addresses separation of concerns at the code level. In this paper, we argue for supporting aspects in MDA. We propose an approach wherein different aspects can be specified using different modeling notations and propose model transformations as a mechanism for weaving them. We discuss several issues including tool support that need to be investigated in order to support multi-dimensional separation of concerns in MDA.