RLinda: A Petri Net Based Implementation of the Linda Coordination Paradigm for Web Services Interactions

摘要

The core functionality of Web-service middlewares tries to wrap existing business logics and make them accessible as Web services. Recently, well-known standardization initiatives have proposed some high-level declarative languages for the description of coordination protocols and the implementation of coordination middlewares. In parallel to these initiatives, an increasing interest on the use of classical coordination models on distributed environments has been shown. In this work we present a Linda-like coordination framework using Petri nets, which is executed by the Renew tool, a high-level Petri net interpreter developed in Java, and subsequently exposed as a Web service able to be used by other services for coordination purposes. The implementation is based on an extension of the original Linda model that improves the tuple representation capabilities and extends the matching functions used for the recovery of tuples from the coordination space. The efficiency of the proposed implementation has been empirically evaluated on a cluster computing environment, and its performances compared with the previously reported ones related to JavaSpaces.