Coordination in a Reflective Architecture Description Language

Abstract

Software Architecture studies the structure of software systems, as described by Architecture Description Languages (Adls). When these capture structures of change, they are comparable to Coordination Languages. Previous work suggests that the combination with Reflection concepts renders a general framework for the description of such evolving structures. This paper describes a reflective Adl named PiLar designed to provide such a framework. It consists of a structural part, which describes the static skeleton, and a dynamic part, which defines patterns of change. The major novelty is the reification relationship, which structures a description in several meta-layers, such that the architecture is able to reason and act upon itself. The paper includes a complete PiLar example, to show the language’s use and some of its most relevant features. It describes a Tuple Space model, illustrating the analogy with existing Coordination Models. We conclude by emphasizing PiLar’s generality and applicability.

This work has been partially sponsored by the Spanish Comission of Science and Technology through the CICYT Project TEL99-0335-C04-04, and by the Autonomous Government of Castilla and León through the Project JCYL VA61/00B.