A position paper presented at the 1998 International Workshop on Component-Based Software Engineering

Abstract

Most of the current concurrent object-oriented approaches do not address the issue of separation of concern between synchronization and scheduling controls inside the concurrent objects. This paper presents a concurrent object-oriented model in which a concurrent object, which represents a shared resource abstraction in our model, is decomposed into a hierarchy of abstractions: a shared data abstraction, a synchronization abstraction, and a scheduling abstraction. It will be shown that the separation of concern among the three major components of the concurrent objects avoids many of the conceptual difficulties that arise when integrating concurrency into object-oriented paradigm. Our model provides explicit, declarative, and reusable first class components for synchronization and scheduling controls as it has been the case for data and operations in the sequential object-oriented languages. The notion of scheduling policy inheritance in our model facilitates the process of engineering adaptability in the development of the intelligent reactive/adaptive systems.

keywords: concurrent object-oriented programming, soft-real-time/adaptive systems, reuse, synchronization constraints, scheduling protocols, adaptive-arena