Co-evolving Annotations and Source Code through Smart Annotations

Annotations are a means to attach additional meta data to the source code of a system. Nowadays, more and more technologies rely on the presence of such annotations in the source code: beyond their use for documentation purposes, annotations impact the behaviour of the system. Since there exists little or no support to make sure that upon evolution of the system, the source code remains correctly annotated, source code can become miss-annotated. This in turn, can result in erroneous behaviour. In this paper we present Smart Annotations, an approach for co-evolving source code and annotations. Our approach enables developers to constrain the use of annotations in the source code and offers tool support to identify conflicts between source code and annotations. To illustrate the use of our approach, we demonstrate its applicability using examples from the domain of aspect-oriented programming and Enterprise Java Beans.