Is there any requirement for DOM used to create a DominoTree, such as being namespaceaware or created with level 2 dom builder?

Question

We are adding code to convert a DOM to Domino before invoking saxon library to process xquery expression, which involves constructing a xml document as output. Following exception is seen, for DOM created using certain DOM builders:

java.lang.NullPointerException
    at net.sf.saxon.om.NameOfNode.equals(NameOfNode.java:177)
    at net.sf.saxon.om.SingletonAttributeMap.put(SingletonAttributeMap.java:69)
    at net.sf.saxon.om.NodeInfo.attributes(NodeInfo.java:528)
    at net.sf.saxon.tree.util.Navigator.copy(Navigator.java:673)
    at net.sf.saxon.om.NodeInfo.copy(NodeInfo.java:568)
    at net.sf.saxon.tree.util.Navigator.copy(Navigator.java:679)
    at net.sf.saxon.om.NodeInfo.copy(NodeInfo.java:568)
    at net.sf.saxon.event.ComplexContentOutputter.decompose(ComplexContentOutputter.java:860)
    at net.sf.saxon.event.ComplexContentOutputter.append(ComplexContentOutputter.java:656)

The cause seems to be that node.getLocalName() for attribute type of nodes, returns null for Domino. Same setup works if DOM is converted to Tiny Tree or passed using a DOMWrapper to Saxon.

Xquery using domino, expected to work, threw Exception.

but the same model, works while using TinyTree and DOM. Are things different with Domino? — jmashalk, Nov 03 '22 at 14:24
I think only Michael Kay can answer that, so you have to wait until he shows up here or, if it is urgent, perhaps delete your StackOverflow question and try to raise an issue at https://saxonica.plan.io/projects/saxon/issues. — Martin Honnen, Nov 03 '22 at 14:44

score 0 · Answer 1 · answered Nov 10 '22 at 10:31

You've raised this on the Saxonica support forum at https://saxonica.plan.io/issues/5727

To summarise:

(a) Whether using the DOM wrapper in Saxon, or the Domino structure (which adds extra indexing), the DOM should be namespace-aware and should be constructed using namespace-aware (i.e. level-2) interfaces.

(b) If you don't follow that rule, we shouldn't crash (so we'll fix the crash that you've observed), but we can't guarantee delivering XPath-conformant results. The mapping from a non-namespace-aware DOM to a valid XDM instance is undefined and unpredictable, so the results of XPath processing are undefined. This might mean, for example, that when the result is serialized, it's not well-formed XML (for example, it might contain undeclared prefixes in element or attribute names.

Is there any requirement for DOM used to create a DominoTree, such as being namespaceaware or created with level 2 dom builder?

1 Answers1