Engineering Accessible Web Applications. An Aspect-Oriented Approach

The development of accessible Web software is complicated for several reasons. Though some of them are technological, the majority are related with the need to compose different and, many times, unrelated design concerns which may be functional as in the case of most of the specific application's requirements, or non-functional such as Accessibility itself. In this paper, we present a novel approach to conceive, design and develop Accessible Web applications in an aspect-oriented manner. In order to reach our goal, we provide some modeling techniques that we specifically developed for handling the non-functional, generic and crosscutting characteristics of the Accessibility concerns. Specifically, we have enriched User Interaction Diagrams with integration points, which are used to reason and document Accessibility for activity modeling during user interface design. Then by instantiating a Softgoal Interdependency Graph template with association tables, we work on an abstract interface model (composed by ontology widgets) to obtain a concrete and accessible interface model for the Web application being developed. We use a real application example to illustrate our ideas and point out the advantages of a clear separation of concerns throughout the development life-cycle.