A Document-Oriented Paradigm for the Construction of Content-Intensive Applications

In this paper we describe our work on the formulation of a document-oriented paradigm for improving the construction and maintenance of content-intensive applications (i.e. applications that make intensive use of the information provided by the experts in a given domain: the contents). According to this paradigm, the development of a content-intensive application must be the result of close collaboration between two kinds of actors: domain experts and developers. The goal of this collaboration is the authoring of (i) a set of documents describing the most relevant aspects of the application (i.e. the contents and other relevant customizable features); (ii) a grammar describing a domain-specific markup language that will be used to make the structure and the data in these documents explicit and (iii) a suitable processor for this language. The final running application will be automatically produced by processing the marked documents with this processor. The use of this paradigm in the development of content-intensive applications can increase the initial cost of application production, but in the long run it can substantially improve maintenance and portability, and promote information and software reuse as well. We have successfully applied this paradigm to the development of educational and hypermedia applications, and knowledge-based systems. From these experiences, we have found that the feasibility of the paradigm depends to a great extent on having mechanisms that enable the incremental definition of the markup languages and the incremental construction of their processors. This has led us to the formulation of a document-oriented approach for the development of content-intensive applications tightly coupled with these principles of incremental formulation and operationalization of domain-specific markup languages.