Exploiting Ontologies To Deploy User-Friendly and Customized Metadata Editors

The Model-View-Controller is a well known architectural pattern, derived from software engineering theories, that provides a clear separation between three dimensions: “how data is modelled” (model), “how the model is shown in output (view)” and “how input events affect the inner state of the model (controller)”. In this paper we employ the MVC pattern as the basic principle for the implementation of a sophisticated, user-friendly, generic, customizable metadata editor. The flexibility of the MVC approach is shown in Gaffe (Generator of Automatic Form - Final Edition), a metadata editor that uses different OWL ontologies to create custom forms for the input of instance values for an ontological metadata schema. The separation of the ontologies makes it possible to create metadata editors for any schema, and to customize the forms themselves to provide the best user experience in filling in the required metadata values. Gaffe exists in two different implementations: Gaffe for Word Processor (an Open Office and Microsoft Office plug-in) and Ontological Wiki (a MediaWiki plug-in), used to embed structured values to an electronic document according to the corresponding syntax. Forms are fully customizable both in appearance (supporting a variety of widget types, as well as grouping, labelling and positioning) and in help features (such as default values, warning messages, pre-processed proposed values, validity verification, etc.).