THE SWS MEDIATOR WITH WEBML/WEBRATIO AND
JABC/JETI: A COMPARISON
Tiziana Margaria
, Christian Winkler
, Christian Kubczak
, Bernhard Steffen
Institute for Informatics, University of Potsdam, 14482 Potsdam, Germany,
Department of Computer Science, University of Dortmund, 44227 Dortmund, Germany,
Marco Brambilla
, Stefano Ceri
, Dario Cerizza
§
, Emanuele Della Valle
§
, Federico M. Facca
, Christina Tziviskou
Dipartimento di Elettronica e Informazione, Politecnico di Milano, Milano, Italy
§
CEFRIEL, Milano, Italy
Keywords:
Semantic Web, Web services, jABC, WebML.
Abstract:
In this paper we compare the SWS Challenge Mediator solutions provided using the WebML/Webratio and
the jABC/jETI approaches.
1 INTRODUCTION
In this paper we compare two solutions to the medi-
ation scenario of the SWS challenge
1
that are based
on the use of WebML (Ceri et al., 2002) and of the
jABC (Steffen et al., 2006; jABC Website, 2007) as
modelling and execution platforms.
We compare only the solutions to the first version
of the SWS Challenge scenario, since the jABC solu-
tion was discussed at the SWS review workshop only
for this first Phase. Nevertheless, the technical com-
parison of the approaches is of general interest and
valid also for the second phase of the scenario.
Both groups adopt a model based approach, sup-
ported by model driven design tools and environ-
ments. This allows modelling the mediator in a graph-
ical high level modelling language and supports the
derivation of an executable mediator from these mod-
els. The solutions are thus similar in their spirit, and
we provide here a first description and comparison of
the similarities and differences, at the modelling, lan-
guage, tool, and change management levels.
In the following, we briefly describe the two con-
crete solutions (Sect. 2 and 3) from the point of view
of the used technologies, then we sketch a comparison
(Sect. 4), we present a reduction of the two solutions
to their mere, common essence (Sect. 5), and finally
we conclude in Sect. 6.
1
http://sws-challenge.org
2 WEBML
The specification of a WebML application (Ceri et al.,
2002) consists of a set of models: the application data
model (an extended Entity-Relationship model), one
or more hypertext models (i.e., different site views
or different service views), expressing the navigation
paths and the page composition of the Web applica-
tion or the chain of operations needed to describe a
Web service; the presentation model, describing the
visual aspects of the pages for user views. WebML
covers also the development of B2B Web applica-
tions implementing business processes, thereby sup-
porting full-fledged collaborative workflow-based ap-
plications, spanning multiple individuals, services,
and organizations. In such case the service view or
site view is partially generated by a BPMN model
representing the workflows involved in the applica-
tion. The core elements of a WebML diagram are
units. Each WebML unit has its own well defined
semantic and its execution complies with its seman-
tic. The composition of different units leads to the
description of the semantic of hypertext or Web ser-
vices. WebML provides standard units for querying
data (e.g. Index unit, Selector unit), modifying
data (e.g. Modifying unit). The WebML conceptual
model has been also extended with a service model
that includes a set of Web service units (Manolescu
et al., 2005), corresponding to the WSDL classes of
422
Margaria T., Winkler C., Kubczak C., Steffen B., Brambilla M., Ceri S., Cerizza D., Della Valle E., M. Facca F. and Tziviskou C. (2007).
THE SWS MEDIATOR WITH WEBML/WEBRATIO AND JABC/JETI: A COMPARISON.
In Proceedings of the Ninth International Conference on Enterprise Information Systems, pages 422-429
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