Implementing Federated Object Systems

Abstract

Abstract. With the increase of automatically sensed and generated data in distributed software systems, the publish/subscribe paradigm gains importance. Automatically generated notifications are pushed from their publishers to interested subscribers. Interoperability is a core issue in such federated networked distributed applications. However, the problems of heterogeneity must be reconsidered in the light of tougher conditions than previously: low latency delivery in addition to expressiveness and extensibility. To aid in engineering federated distributed systems, this paper proposes a framework for object transformations. Components can operate in individual, semantic contexts, which include local type declarations, finegrained transformation rules (t-rules), and type mappings that express the programmer's intent at a high level. Our generic approach supports transformations at any granularity using clear priorities to select among complementary t-rules. We present empirical evidence of the efficiency of our approach and of the benefits to the programmer in terms of code quality.