DeepCompare: static analysis for runtime software evolution
Yves Vandewoude, Yolande Berbers · 2005
Due to their modular design, component-based applications are relatively well-suited to supporting run-time evolution. However, replacing a component at run time without halting the application remains a difficult task. The main cause of this complexity can be found in transferring the state between two versions of a component. We have developed a methodology to perform run-time adaptations on component-based applications. This paper briefly introduces our methodology and then continues with a detailed study of our approach to state transfer. By exploiting the strong encapsulation of components, we conduct an analysis of the (object-oriented) source code of different versions of a component. A classification is presented which introduces different categories of change, according to the impact of the change on the set of objects that make up the component. We then describe different heuristics that are used to identify equivalent data structures between different versions. We show how these techniques are implemented in a tool called DeepCompare. An evaluation of our tool using two examples (an academic toy component and a real-life application), demonstrates that our process successfully identifies the vast majority of corresponding structures in a typical evolution scenario.