A Software Engineering Framework for Context-Aware Service-Based Processes in Pervasive Environments - Advanced Design Approaches to Emerging Software Systems - page 104

ties and demanding minimal attention from the
user. Context-aware applications aims to meet
these objectives or requirements by adapting to a
subset of the current context considered relevant
to the task at hand such as the user location,
time, and user activity. In this chapter we focus
on developing context-aware service-based pro-
cesses applications. In addition, we define the
context-aware process adaptation as the action that
modifies the process in a way that causes process
behavior to evolve according to the evolution of
business and users' requirements, and the context
considered relevant to that process . To this end,
process modeling must be flexible enough to deal
with constant changes - both at the business level
(e.g. evolving business rules) and the technical
level (e.g. contextual information and platform
upgrades). The flexibility could be provided or
addressed by incorporating variabilities into a
system (Koning et al. 2009). Therefore, the notion
of an evolution fragment and evolution primitive
that capture the process variability in a logical
way are introduced.
Secondly, in order to have the transition of the
context-aware applications out of the laboratory
to the marketplace, there is a need for a software
engineering framework that simplifies the design
and implementation of context-aware software.
To this end, the approach proposed in this chapter
could apply an adaptation to processes modeled
or developed without any adaptation possibility in
mind and independently of specific usage contexts.
In addition, it supports the viewpoint of context-
aware adaptation as a crosscutting concern with
respect to the core “business logic” of the process.
In this way, the design of the process core can be
decoupled from the design of the adaptation logic
which significantly eases the process design and
rapid prototyping.
Thirdly, to ease the development of such appli-
cations it is necessary to decouple the application
from context acquisition and representation, and

at the same time provide universal models and
mechanisms to manage context. Thus, generic
and dynamically manageable context models are
of interest since they can be reused by different
applications and ease context sharing between
systems (Chen et al. 2004). Therefore, in this
chapter, we present a context management infra-
structure based on a flexible product line based
context model which significantly enhances
reusability of context information by providing
context variability constructs to satisfy different
application needs.
The rest of the chapter is organized as fol-
lows: In “Context Management Framework,” the
context management infrastructure is described.
It this section the conceptual model for context
management is introduced as well as the ratio-
nale behind it; then we describe how to model
the context information considering the applica-
tion requirement perspective. For this purpose
we leverage ideas from software product line
techniques. In “A Model-Driven Framework
for Managing Context-Aware Adaptive Service-
Based Processes,” a MDD-based (Model-Driven
Development) framework called Apto (Latin word
for Adapt) is introduced. We show how to capture
the variability in the service-based process in a
logical form by introducing the notion of context
fragments and context primitives. The proposed
approach contributes to a solution to automati-
cally generating a customized process based on
the context. Another feature is that Apto supplies
a set of automated tools for generating and de-
ploying executable process definitions e.g. WS-
BPEL (OASIS, 2007) which in turn significantly
reduces the development cost. In “Case Study,”
we illustrate the proposed frameworks by giving
a simple example of Conference Event Advisor
process. The related work and concluding remarks
ends the chapter.