XOM API for Processing XML with Java

[peter murray-rust <pm286 AT cam.ac.uk>]

[Please excuse me if this has been discussed before and is an FAQ]

I make frequent use of constructs such as

<cml xmlns="http://www.xml-cml.or/schema";
  xmlns:xsd="http://www.w3.org/2001/XMLSchema";>
  <scalar dataType="xsd:double">1.23</scalar>
</cml>

where attribute values are effectively QNames. The namespace spec 
(http://www.w3.org/TR/REC-xml-names/) states (5.1) that:
"The namespace declaration is considered to apply to the element 
where it is specified and to all elements within the content of that element".
I therefore assumed that in the example the xsd namespaceURI 
(http://www.w3.org/2001/XMLSchema) is in scope for the dataType 
attribute. However the XOM documentation implies that the namespace 
is not in scope and that the implementer has to explore the ancestry 
every time to determine what namespaces are actually in scope. A 
possible solution is to cache the namespace on the appropriate 
elements but this could be fragile as it could break if elements are 
detached or moved.

Is the XOM interpretation consistent with the spec and other DOM 
implementations?

Personally as a user of XOM I would find it much easier if all 
namespaces were easily available in all their descendant elements.

Thanks

P.



Peter Murray-Rust
Unilever Centre for Molecular Sciences Informatics
University of Cambridge,
Lensfield Road,  Cambridge CB2 1EW, UK
+44-1223-763069