I am parsing an XML document and want to enable validation. The
document is a JCA resource adapter deployment descriptor. In JCA 1.0
the deployment descriptor is specified via a DTD. In JCA 1.5 it is
specified by an XML schema. I have the following code:

public Document getXMLDocument(String fileName, boolean validation) {

   Document result = null;
   try {
       DocumentBuilderFactory parserFactory =
DocumentBuilderFactory.newInstance();
       parserFactory.setValidating(true);

//parserFactory.setAttribute("http://java.sun.com/xml/jaxp/properties/schemaLanguage",,
       //                       "http://www.w3.org/2001/XMLSchema");
       }
       DocumentBuilder parser = parserFactory.newDocumentBuilder();
       result = parser.parse(new File(fileName));
   } catch (SAXException se) {
       System.err.println(se.getMessage());
   }
   return result;
}

The DTD-specified document parses successfully but the schema-specified
document throws a SAXParseException with the message "Document is
invalid: no grammar found".

If I remove the commented out code, the schema-specified document
parses successfully but the DTD-specified document throws a
SAXParseException with the message "cvc-elt.1: Cannot find the
declaration of element 'connector'."

Other than scanning the file for <!DOCTYPE and conditionally setting
the schema language, is there any way to parse an XML document with
validation regardless of whether it is schema- or DTD-specified?

Kevin