Dynamic Interface Adaptability in Service Oriented Software

This paper deals with the adaptability in the context of service oriented systems. Static adaptability means simply the modification of the system constituents in response to new needs or situations. Whereas dynamic adaptability requires that modifications must be done at run-time without stopping the system and without affecting its consistency and integrity which is a very complicated task. A dynamic system can be closed or open; an open system can be either adaptive or self-adaptive. Another comparison criteria between dynamic systems can be the mechanisms used to support the dynamic adaptability: reflection, reification, mediators, plugins and so on. It is often said that the different entities composing a service oriented system are independent, however this is not exactly true because clients need to know at as early as compile-time the services they have to use. Two main limitations of service oriented systems are discussed in this paper: syntactic dependencies and the lack of real automated dynamic support. The proposed solution is implemented for OSGi framework, it enhances the clients/servers independency as well as the dynamic character of systems.