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TOWARD REUSABILITY IN WEB MODELING
Using QVT Relations
Ali Fatolahi, Stéphane S. Somé and Timothy C. Lethbridge
School of Information Technology and Engineeing, University of Ottawa, 800 King Edward, K1N 6N5, Ottawa, Canada
Keywords: MDD, QVT, Web, Reusability, Meta-model.
Abstract: In this paper, a model-driven approach for web development is presented. The approach contains two
important elements that serve reusability: an abstract model and a set of transformations. Transformations
act as the chaining feature of model-driven development (MDD); that is transformations add to the value of
models by transforming them to those of the desired type. As a standard for developing transformations,
QVT relations are used in this paper to specify mappings from a high-level model to an abstract model of
web-based applications. This model is abstract since it does not rely on any specific web platform but on the
common features of web applications. Having this model and its corresponding transformations, model-
driven web development for specific platforms becomes faster and more reusable.
1 INTRODUCTION
Models form the value of model-driven development
(MDD) methods. Transformations add to the value
of MDD by processing raw models and by creating
more detailed ones that could be used for the
development of actual applications. We aim at
maximizing the level of value re-use as well as
minimizing the length of transformations that create
value or add to it. Thus, we present an abstract
model of web applications that is reusable for
several web platforms as well as a set of QVT
relations to transform requirements to the abstract
web models.
We have added an intermediate level termed
Abstract PSM (APSM) to the three conventional
levels of MDA, i.e. CIM, PIM and PSM. The
APSM, an intermediate between the PIM and PSM
in the context of Web applications, is concerned
with models specified with respect to common
features of different web platforms. The APSM is
platform-specific in the sense that it describes
features specific to the abstract web platform; it is
also abstract since it does not contain details of
specific web platforms but only their shared
features. Two sets of transformations are needed
from PIM to PSM: one to map PIM to APSM and
the second one to map APSM to PSM.
An important aspect of our work is the usage of
QVT relations as a means of formalizing model-
driven transformations. In this paper, we present an
approach based on QVT relations to be used for the
generation of APSM models. Hence, the PIM-to-
APSM part of the transformations could be re-used
for all applications. Only the QVT relations required
for generating a specific PSM from the APSM need
to be supplied. Since the APSM is semantically
closer to PSMs, this latter part is easier to develop in
comparison to the conventional PIM-to-PSM
transformations.
The importance of web applications as well as
the ever-increasing volatility of web technologies
postulates the need to benefit from models that have
been created for previous projects. In order to
achieve this, one needs either web models that are
adaptable with virtually any platform or automated
transformations that enable transforming models of
different platforms to each other. In this paper, we
use a combination of the two.
The APSM, which is used as the abstract web
model in this paper, is a reusable model because it
can be used to describe models of web applications
regardless of their platforms. Hence for example, the
APSM of a web application once deployed using a
.Net-based technology could be reused to create the
same application using a GWT-based framework as
well.
Also, the transformations that map the APSM to
specific platforms come in handy here. These
facilitate model reuse by relieving the developer
383
Fatolahi A., S. Somé S. and C. Lethbridge T..
TOWARD REUSABILITY IN WEB MODELING - Using QVT Relations.
DOI: 10.5220/0003290703830386
In Proceedings of the 7th International Conference on Web Information Systems and Technologies (WEBIST-2011), pages 383-386
ISBN: 978-989-8425-51-5
Copyright
c
2011 SCITEPRESS (Science and Technology Publications, Lda.)