An Eclipse-Based Web Service Composition Tool

A Presentation for Faculty and Students at

Computer Science Dept.

California State University, Los Angeles

Candidate: Martin J. Olsen

Advisor: Dr. Jiang Guo

As part of Master Thesis Requirements. (CS 599B)

Date: 03/19/2007

Agenda

Introduction Demo System architecture Design and implementation Future work Conclusion References Q & A!

Introduction

Abstract: “A graphical plug-in for Eclipse, where the user can create and execute Web Service Compositions.” (Picture 1)

Technologies: Java, Apache Axis, WSDL4J, JWSDL, Eclipse, Eclipse GEF, WSIF, BPEL4WS, BPWS4J.

Web Service Composition: “Define business processes that interact with external

entities through Web Service operations defined using WSDL 1.1, and that manifest themselves as Web services defined using WSDL 1.1.” [1]

“The problem of composing autonomous services to achieve new functionality.” [2]

Demo

1. Creating a new composition2. Different elements of the graphical plug-in

The Palette The Stage Properties view Model Elements

3. Executing the Composition A perfect composition Error handling!

Click for video demo!

System Architecture – Eclipse SDK

Eclipse SDK consists of a kernel and standard plug-ins. “Everything in Eclipse is a plug-in.”

Third party plug-ins can be loaded into Eclipse also. Plug-ins can be extended

Implement plug-in interfaces Plug-in Manifest file

Plug-in extends: Eclipse Workspace Eclipse Workbench Eclipse GEF (3rd party)

System Architecture – Web Services

Client Framework – Apache AxisSoap engine/implementationXML-based communication and

encoding format Server Framework

Apache TomcatApache Axis

System Architecture – Plug-in Overview

System Architecture - Traversal

Traversal Algorithm1. Find root.

2. Output of element -> Input of next element

3. Invoke

4. Successful -> (Goto 2)

Failure -> End

System Architecture – Eclipse GEF

Eclipse GEF - a typical MVC framework. (Struts, Spring)

Design and implementation – The model

Design and implementation – Retrieving the Model

Design and implementation – Invoking the Model

Future Work – Data Mapper

Future Work – Invoke Element

Future Work - UDDI

Conclusion

Creating a plug-in is a meticulous process. Requires understanding of: Eclipse SDK Eclipse GEF Web Services, AXIS Other Frameworks, WSIF, WSDL4J

Puzzling it all together has required every part of previous knowledge, motivation and creativity.

Successful implementation.

References

[1] BPEL, Wikipedia

http://en.wikipedia.org/wiki/BPEL

[2] SWORD, A developer toolkit for Web Service Composition

http://www2002.org/CDROM/alternate/786/