XML Specification and Its Implementations

Since XML is a specification and not a technology, technologies which work with XML are implemented different. This is most evident in the new technologies like Semantic Web and Services Oriented Architecture (SOA) which extensively use XML. For example:

Semantic Web
In November 2007, I attended an ontology conference in Columbia, MD. During the conference, Steven Robertshaw stated that there is no standard ontology editor since each editor renders, validates a OWL document differently. OWL is a W3C standard for ontologies. I agree with Robertshaw's statement because the OWL document which I created from Protege did not validate on Altova's SemanticWorks OWL editor. When I fixed the OWL document for the SemanticWorks tool then it wouldn't work on Protege.

Web Services
Altova's XMLSpy generated WSDL does not validate well on Cape Clear's WSDL editor called SOAEditor. WSDL is a W3C approved XML specification for web service contracts. Sometimes certain editors look for attributes in a different place. I have used Mindreef's SoapScope to test a WSDL which is approved by all WSDL editors.

XML Schemas
While I was doing in depth analysis on Global Justice XML Data Model (GJXDM) for Department of Homeland Security, I created XML Schemas using XMLSpy . This caused a major issue in XMLSpy editor. The graphical interface stated the the xsd was valid however the xsd was invalid in the text view. After some research, I determined that XMLSpy used multiple xsd validators and that each XMLSpy view used a different xsd validator. This is still a problem. Look at this article.

Going back to my last blog entry, XML based modeling technologies have too many quirks and this is because how the technologies have implemented various XML specifications. This type of confusion is NOT needed by a data modeler. Before I start any modeling exercise, I would say, "Where is my Protege? "