import of schema with DOCTYPE declaration

[Bill Michell <bi...@bbc.co.uk>]

I'm trying to get xerces-j version "Xerces-J 2.1.0" (as embedded in Apple's WebObjects 5.2.2 - my application's standard platform) to parse and validate an XML document using a specific XML Schema, through jaxp calls.

Unfortunately the Schema document is not under my control (though I can make a local copy and tune it, of course).

I'm using the following code to set up a DocumentBuilder which will validate against the schema document:
	public static DocumentBuilderFactory documentBuilderFactory(String schemaUrl) {
		DocumentBuilderFactory factory=DocumentBuilderFactory.newInstance();
		factory=DocumentBuilderFactory.newInstance();
		factory.setCoalescing(true);
		factory.setExpandEntityReferences(true);
		factory.setNamespaceAware(true);
		factory.setIgnoringComments(false);
		factory.setIgnoringElementContentWhitespace(false);
		factory.setValidating(true);
		factory.setAttribute(
			"http://java.sun.com/xml/jaxp/properties/schemaLanguage",
			"http://www.w3.org/2001/XMLSchema");
		factory.setAttribute(
			"http://java.sun.com/xml/jaxp/properties/schemaSource",
			schemaUrl);
		return factory;		
	}

My problem is that the parsing fails with the following exception:
[2003-12-18 16:37:39 GMT] <WorkerThread0> src-import.0: Failed to read imported schema document 'http://www.w3.org/2001/03/xml.xsd'.
[2003-12-18 16:37:39 GMT] <WorkerThread0> src-resolve: Cannot resolve the name 'xml:lang' to a(n) attribute declaration component.
org.xml.sax.SAXParseException: src-resolve: Cannot resolve the name 'xml:lang' to a(n) attribute declaration component.
	at org.apache.xerces.util.ErrorHandlerWrapper.createSAXParseException(ErrorHandlerWrapper.java:232)
	at org.apache.xerces.util.ErrorHandlerWrapper.error(ErrorHandlerWrapper.java:173)
	at org.apache.xerces.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:371)
	at org.apache.xerces.impl.xs.traversers.XSDHandler.reportSchemaError(XSDHandler.java:1937)
	at org.apache.xerces.impl.xs.traversers.XSDHandler.getGlobalDecl(XSDHandler.java:1046)
	at org.apache.xerces.impl.xs.traversers.XSDAttributeTraverser.traverseLocal(XSDAttributeTraverser.java:126)
	at org.apache.xerces.impl.xs.traversers.XSDAbstractTraverser.traverseAttrsAndAttrGrps(XSDAbstractTraverser.java:412)
	at org.apache.xerces.impl.xs.traversers.XSDComplexTypeTraverser.traverseSimpleContent(XSDComplexTypeTraverser.java:547)
	at org.apache.xerces.impl.xs.traversers.XSDComplexTypeTraverser.traverseComplexTypeDecl(XSDComplexTypeTraverser.java:270)
	at org.apache.xerces.impl.xs.traversers.XSDComplexTypeTraverser.traverseLocal(XSDComplexTypeTraverser.java:165)
	at org.apache.xerces.impl.xs.traversers.XSDElementTraverser.traverseNamedElement(XSDElementTraverser.java:335)
	at org.apache.xerces.impl.xs.traversers.XSDElementTraverser.traverseGlobal(XSDElementTraverser.java:226)
	at org.apache.xerces.impl.xs.traversers.XSDHandler.traverseSchemas(XSDHandler.java:938)
	at org.apache.xerces.impl.xs.traversers.XSDHandler.parseSchema(XSDHandler.java:395)
	at org.apache.xerces.impl.xs.XMLSchemaLoader.loadSchema(XMLSchemaLoader.java:490)
	at org.apache.xerces.impl.xs.XMLSchemaLoader.processJAXPSchemaSource(XMLSchemaLoader.java:589)
	at org.apache.xerces.impl.xs.XMLSchemaLoader.loadSchema(XMLSchemaLoader.java:488)
	at org.apache.xerces.impl.xs.XMLSchemaValidator.findSchemaGrammar(XMLSchemaValidator.java:2287)
	at org.apache.xerces.impl.xs.XMLSchemaValidator.handleStartElement(XMLSchemaValidator.java:1781)
	at org.apache.xerces.impl.xs.XMLSchemaValidator.startElement(XMLSchemaValidator.java:588)
	at org.apache.xerces.impl.XMLNamespaceBinder.handleStartElement(XMLNamespaceBinder.java:877)
	at org.apache.xerces.impl.XMLNamespaceBinder.startElement(XMLNamespaceBinder.java:569)
	at org.apache.xerces.impl.dtd.XMLDTDValidator.startElement(XMLDTDValidator.java:727)
	at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanStartElement(XMLDocumentFragmentScannerImpl.java:759)
	at org.apache.xerces.impl.XMLDocumentScannerImpl$ContentDispatcher.scanRootElementHook(XMLDocumentScannerImpl.java:957)
	at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(XMLDocumentFragmentScannerImpl.java:1544)
	at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:329)
	at org.apache.xerces.parsers.DTDConfiguration.parse(DTDConfiguration.java:525)
	at org.apache.xerces.parsers.DTDConfiguration.parse(DTDConfiguration.java:581)
	at org.apache.xerces.parsers.XMLParser.parse(XMLParser.java:152)
	at org.apache.xerces.parsers.DOMParser.parse(DOMParser.java:253)
	at org.apache.xerces.jaxp.DocumentBuilderImpl.parse(DocumentBuilderImpl.java:201)
<snip rest of stack trace>

By examining the schema documents, I find:
The main schema document contains the element:
<xs:import namespace="http://www.w3.org/XML/1998/namespace" schemaLocation="http://www.w3.org/2001/03/xml.xsd"/>

I believe this is so that we can use xml:lang attributes within the elements that we are defining.

http://www.w3.org/2001/03/xml.xsd contains the declaration:
<!DOCTYPE xs:schema PUBLIC "-//W3C//DTD XMLSCHEMA 200102//EN" "XMLSchema.dtd">

If I delete this <DOCTYPE> declaration from a local copy of xml.xsd, my exception goes away. Changing the path so that it explicitly points to a local copy of XMLSchema.dtd doesn't help. Neither does changing the path to explicitly point to a file on the w3 server.

Would someone please be kind enough to point me in the right direction.

-- 
Bill Michell


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