Integration of relational database metadata and XML technology to develop an abstract framework to generate automatic and dynamic web entry forms.

摘要

Developing interactive web application systems requires a large amount of effort on designing database, system logic and user interface. These tasks are expensive and error-prone. Web application systems are accessed and used by many different sets of people with different backgrounds and numerous demands. Meeting these demands requires frequent updating for Web application systems which results in a very high cost process. Thus, many attempts have been made to automate, to some degree, the construction of Web user interfaces. Three main directions have been cited for this purpose. The first direction suggested of generating user interfaces from the application¿s data model. This path was able to generate the static layout of user interfaces with dynamic behaviour specified programmatically. The second tendency suggested deployment of the domain model to generate both, the layout of a user interface and its dynamic behaviour. Web applications built based on this approach are most useful for domain-specific interfaces with a relatively fixed user dialogue. The last direction adopted the notion of deploying database metadata to developing dynamic user interfaces. Although the notion was quite valuable, its deployment did not present a generic solution for generating a variety of types of dynamic Web user interface targeting several platforms and electronic devices. udThis thesis has inherited the latter direction and presented significant improvements on the current deployment of this tendency. This thesis aims to contribute towards the development of an abstract framework to generate abstract and dynamic Web user interfaces not targeted to any particular domain or platform. To achieve this target, the thesis proposed and evaluates a general notion for implementing a prototype system that uses an internal model (i.e. database metadata) in conjunction with XML technology. Database metadata is richer than any external model and provides the information needed to build dynamic user interfaces. In addition, XML technology became the mainstream of presenting and storing data in an abstract structure. It is widely adopted in Web development society because of its ability to be transformed into many different formats with a little bit of effort. This thesis finds that only Java can provide us with a generalised database metadata based framework. Other programming languages apply some restrictions on accessing and extracting database metadata from numerous database management systems. Consequently, JavaServlets and relational database were used to implement the proposed framework. In addition, Java Data Base Connectivity was used to bridge the two mentioned technologies. udThe implementation of our proposed approach shows that it is possible and very straightforward to produce different automatic and dynamic Web entry forms that not targeted at any platform. In addition, this approach can be applied to a particular domain without affecting the main notion or framework architecture. The implemented approach demonstrates a number of advantages over the other approaches based on external or internal models.