XOM API for Processing XML with Java

[Elliotte Rusty Harold <elharo AT metalab.unc.edu>]

At 12:25 PM +0100 2/7/03, Laurent Bihanic wrote:
> Hi,
>
> It is not possible to retrieve the default namespace URI using 
> getNamespaceURI("") if the current element has at least one 
> attribute not belong to any namespace.
>
> The test case is the following:
> <b xmlns="urn:x-xom:b" id="b">
>    <c:c xmlns:c="urn:x-xom:c" id="c" />
> </b>
>
> Invoking getNamespaceURI("") on element "b" returns "urn:x-xom:b" 
> but invoking getNamespaceURI("") on element "c" returns "".
>
> The problem lies in getLocalNamespaceURI() while scanning attribute 
> namespaces. This method should makes a special case for the empty 
> prefix and avoid checking attribute namespaces in this case.

OK, I'll write a unit test for this one, and make sure it gets fixed 
in this weekend's batch of namespace changes. Thanks for the catch.

> Another problem is the way to handle null prefixes. XOM is not 
> consistent here as some methods check against null prefixes and 
> assume "" (Namespaces.remove()) while others 
> (getLocalNamespaceURI()) do not check and throw 
> NullPointerExceptions.

Let me think about this. The question is whether null should always 
throw the NullPointerException or should always be treated the same 
as the empty string, right? TRhere may be a problem with the Buolder 
receiving SAX events that makes this tricky, but I'll need to 
investigate further.
--

+-----------------------+------------------------+-------------------+
| Elliotte Rusty Harold | elharo AT metalab.unc.edu | Writer/Programmer |
+-----------------------+------------------------+-------------------+
|           Processing XML with Java (Addison-Wesley, 2002)          |
|              http://www.cafeconleche.org/books/xmljava             |
| http://www.amazon.com/exec/obidos/ISBN%3D0201771861/cafeaulaitA  |
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