Quality attribute scenario based architectural modeling for self-adaptation supported by architecture-based reflective middleware

Reflective middleware is proposed for guaranteeing desired qualities of middleware based systems which reside in the extremely open and dynamic Internet. Current researches and practices focus on how to monitor and change the whole system through reflective mechanisms provided by middleware. However, they put little attention on why, when and what to monitor and change because it is very hard for middleware to collect enough knowledge which is usually specific to the whole system. Being an important artifact in software development, software architecture records plentiful design information, especially the considerations for quality attributes of the target system. It is a natural idea to provide reflective middleware with enough knowledge via software architecture. This paper presents a demonstration of the idea. In this demonstration, the self-adaptations can be analyzed in a quality attribute scenario based way and specified by an extended architecture description language. Such knowledge prescribed at the design phase can be used directly by an architecture based reflective middleware which then automatically adapts itself at runtime.