How to query xmlns= with XPath ?

[oroger]

 Hi,

 

I am currently trying the new namespace aware feature added in JasperReports 4.0.1. (see http://jasperforge.org/projects/jasperreports/tracker/view.php?id=4500).

 

It is working fine after patching the JRXmlUtils class as indicated in the issue. 

However, I am having difficulties with a specific case where the dataset root element has an xmlns attribute with no prefix.

 

In that specific case, the XPath query does not return the value. Since I have no prefix for the namespace I siply can get the value.

Has someone already encountered this issue ? 

Code:

<report xmlns="mynamespace">...	<queryString language="xPath">		<![CDATA[/]]>	</queryString>	<field name="report" class="java.lang.String">		<fieldDescription><![CDATA[report]]></fieldDescription>	</field>

[oroger]

 According to the Xalan mainling list (http://old.nabble.com/XPath-with-default-namespace---No-result-tt33285727.html#a33285727) this behavior is expected. I understand why, <report/> and <report xmlns="{ns}" /> are different elements and should be accessed in two distinct ways.

The solution I see would then be to provide a PrefixResolver as explained here : http://www.edankert.com/defaultnamespaces.html.  I can do this by providing a different XalanXPathExecuterFactory that would have a PrefixResolved as attempted in that page http://jasperforge.org/plugins/espforum/view.php?group_id=102&forumid=103&topicid=44911.

The issue for me now is to be able to initialize the resolver with the XML input. At the moment I could just hardcode prefix / namespace mappings in the getNamespaceForPrefix(String prefix) which seems to be used over getNamespaceForPrefix(String prefix, org.w3c.dom.Node namespaceContext).

JAXPPrefixResolver (http://www.docjar.com/html/api/com/sun/org/apache/xpath/internal/jaxp/JAXPPrefixResolver.java.html) does that kind of parsing but needs a namespaceContext at initialization, which is not provided by the Factory.

Post Edited by oroger at 02/09/2012 16:41