Web services, being a power technology for network interoperability, historically rely on XML as a serialization format. Web services' definitions are usually written in Web Services Description Language (WSDL). An ever increasing interest in Semantic Web Services led to the creation of the Semantic Annotations for WSDL and XML Schema (SAWSDL) specification, which finally allows to semantically annotate services' artifacts in a standard manner. The Web Ontology Language (OWL) is a universal language for authoring ontologies that may be perfectly used for this purpose. Such approach requires a usage of two separate languages - XML Schema for message serialization format (syntax) and OWL for annotations (semantic). The second version of Web Ontology Language (OWL 2) brought a possibility to introduce XML-based structural information into an ontology. While this information can't be used directly for serialization purpose*, it is possible and desirable to use it for logical coherence.
OWL2XS is a library that generates an XML Schema, based on provided OWL 2 ontology. The library is distributed under LGPL license and rely on Apache XML Schema 2.0 library for XML Schema generation and Hermit OWL Reasoner for ontology analysis.