Affiliations: Tongji Center of National Engineering Research Center
for High Performance Computer, Department of Computer Science, Tongji
University, Shanghai, P.R. of China | Department of Computer Science, City University of
Hong Kong, 83 Tat Chee Avenue, Hong Kong SAR, P.R. of China | Tongji Center of National Engineering Research Center
for High Performance Computer, Department of Computer Science, Tongji
University, Shanghai, P.R. of China
Abstract: Web Service composition has become increasingly important with more
and more Web Services developed and deployed on the Web. It requires a formal
and clear representation for analysis, design, and implementation. The Business
Process Execution Language for Web Service (BPEL4WS), which is an XML-based
language, provides a good basis to describe Web Service composition. However,
it still lacks a formal, explicit and graphic representation for visual
modeling of the composition process and result. The Object-Process Methodology
(OPM) has been shown to successfully describe the structure and behavior of
systems using an integrated and coherent set of Object-Process Diagrams (OPDs).
It should also be suitable to describe Web Service composition. In this paper
we will discuss the extensions which are necessary to OPM in order to describe
Web Service composition. We propose several mapping rules between BPEL4WS and
OPD that are identical to the rules between Object-Process Language (OPL) and
OPD so that the OPD set can be automatically created from existing BPEL4WS
documents and BPEL4WS documents can be generated from the OPD set
automatically, with some manual work. With the visual and explicit
representation of Web Service composition, it will make the design and
implementation of the composed services easier and more comprehensive.
Keywords: Object-Process Methodology, Web Service Composition
