[AXIOM-441] Unable to parse XML with empty default namespace attribute value with OpenJDK StAX implementation

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.2.13
• Fix Version/s: 1.2.14
• Component/s: API, LLOM
• Labels: patch
• Assignee: Andreas Veithen
• Reporter: Paul Millar
• Created: 12/Nov/12 16:16
• Updated: 14/Nov/12 13:09
• Resolved: 14/Nov/12 08:17

Description

From:

http://www.w3.org/TR/2009/REC-xml-names-20091208/

"The attribute value in a default namespace declaration MAY be empty. This has the same effect, within the scope of the declaration, of there being no default namespace."

Here is a document that demonstrates this:

<?xml version='1.0' encoding='UTF-8'?>
<foo xmlns='http://example.org/'>
<bar xmlns=''>value</bar>
</foo>

The following code snippet (slightly modified from Axiom documentation) uses Axiom to parse a String variable xmlData:

InputStream in =
new ByteArrayInputStream(xmlData.getBytes(Charset.forName("UTF-8")));
OMXMLParserWrapper builder = OMXMLBuilderFactory.createOMBuilder(in);
OMElement documentElement = builder.getDocumentElement();
documentElement.serialize(System.out);
System.out.println();

When given the above XML example, an IllegalArgumentException is thrown:

Exception in thread "main" java.lang.IllegalArgumentException: Namespace URI may not be null
at org.apache.axiom.om.impl.llom.OMNamespaceImpl.<init>(OMNamespaceImpl.java:38)
at org.apache.axiom.om.impl.llom.OMElementImpl.addNamespaceDeclaration(OMElementImpl.java:430)
at org.apache.axiom.om.impl.builder.StAXOMBuilder.processNamespaceData(StAXOMBuilder.java:608)
at org.apache.axiom.om.impl.builder.StAXOMBuilder.populateOMElement(StAXOMBuilder.java:430)
at org.apache.axiom.om.impl.builder.StAXOMBuilder.createOMElement(StAXOMBuilder.java:461)
at org.apache.axiom.om.impl.builder.StAXOMBuilder.createNextOMElement(StAXOMBuilder.java:318)
at org.apache.axiom.om.impl.builder.StAXOMBuilder.next(StAXOMBuilder.java:249)
at org.apache.axiom.om.impl.llom.OMElementImpl.buildNext(OMElementImpl.java:709)
at org.apache.axiom.om.impl.llom.OMNodeImpl.getNextOMSibling(OMNodeImpl.java:121)
at org.apache.axiom.om.impl.traverse.OMChildrenIterator.getNextNode(OMChildrenIterator.java:36)
at org.apache.axiom.om.impl.traverse.OMAbstractIterator.hasNext(OMAbstractIterator.java:69)
at org.apache.axiom.om.impl.util.OMSerializerUtil.serializeChildren(OMSerializerUtil.java:555)
at org.apache.axiom.om.impl.llom.OMElementImpl.internalSerialize(OMElementImpl.java:846)
at org.apache.axiom.om.impl.llom.OMSerializableImpl.serialize(OMSerializableImpl.java:120)
at org.apache.axiom.om.impl.llom.OMSerializableImpl.serialize(OMSerializableImpl.java:108)
at org.apache.axiom.om.impl.llom.OMSerializableImpl.serialize(OMSerializableImpl.java:127)

This looks like a bug.

Cheers,

Paul.