XML Conceptual Modeling Using UML

The eXtensible Markup Language XML is increasingly nd ing acceptance as a standard for storing and exchanging structured and semi structured information With its expressive power XML enables a great variety of applications relying on such structures notably prod uct catalogs digital libraries and electronic data interchange EDI As the data schema an XML Document Type De nition DTD is a means by which documents and objects can be structured Currently there is no suitable way to model DTDs conceptually Our approach is to model DTDs and thus classes of documents on the basis of UML Uni ed Mod eling Language We consider UML to be the connecting link between software engineering and document design i e it is possible to design object oriented software together with the necessary XML structures For this reason we describe how to transform the static part of UML i e class diagrams into XML DTDs The major challenge for the trans formation is to de ne a suitable mapping re ecting the semantics of a UML speci cation in a DTD correctly Because of XML s speci c proper ties we slightly extend the UML language in a UML compliant way Our approach provides the stepping stone to bridge the gap between object oriented software design and the development of XML data schemata