Safe Adaptation of Component Coordination

In the domain of software engineering, the use of software components is now a well established approach. However, it raises problems about the dynamic adaptation of these components to particular users demands. Indeed, these components have been developed with the intent to have a wide range of use, and so they implement functionalities which perhaps do not match precisely enough the demands of specific users.Therefore, we address the adaptation of the coordination between components by means of so-called Moderators. A Moderator is itself a coordination component managing interactions that are described and formalized using Petri nets. More precisely, we study the dynamic adaptation of the coordination rules by means of specific transformations of the Petri nets used to describe a Moderator.Safety properties must be enforced to maintain a consistent cooperation among participants with respect to the requested evolutions of the coordination rules. In particular, an adaptation of the Moderator can be considered safe if it cannot be detected by the participants. We present a computable criterion which enables to check such a satefy property automatically.We illustrate our approach in the context of a computer aided learning system, by adapting the coordination rules for controlling accesses to documents during an examination.