This interface provides an abstract representation of an XML Schema referenced within the WSDL <types> element. For example, via <xs:schema> or <xs:import>. It contains the namespace used as the target namespace of an inlined schema or as the imported namespace of a schema import. It contains a reference to the actual schema definition, represented by org.apache.ws.commons.schema.XmlSchema. It also indicates whether the schema is 'referenceable' by the WSDL, as defined by the schema referenceability rules in the WSDL 2.0 spec.

NOTE: non-XML type systems like DTD are not handled by this interface. They must be handled by WSDL 2.0 extension mechanisms. TODO initially this will be tested with XML Schema. Need to determine if it really is sufficient for other xml-based schema types like Relax NG or if some type of schema extension mechanism is required.