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Run an XPath against an XSLT document

Why is xpath assert broken when I use it on XSLT stylesheets? I have an XSLT stylesheet that I'm unit testing. My stylesheet generates XSLT stylesheets. I am trying to perform xpath asserts on the resulting generated stylesheets and it looks like XMLUnit is of no help to me. I use a valid Xpath that should result in a single hit and I get zero hits with the XMLUnit Xpath assert. So then I changed to use my own implementation of an XpathAssert. In my implementation I delegate to the JDK5 XPath API to check if an xpath exists. That throws errors. Can somebody show me how to execute this XPath, "/xsl:stylesheet/xsl:template[@name = 'foo']/xsl:call-template[@name = 'foo']" against the following XSLT?
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template name="foo">
<xsl:call-template name="foo"/>
</xsl:template>
</xsl:stylesheet>

I realize this is a particularly involved and unique question but I can't find an answer. I've also cross posted on the yahoo Junit group where I've included more detail about my actual code. I forgot that it takes a moment to moderate so now I'm posting here. Any insight is highly appreciated.

Kannan Ekanath

I am not sure if you can evaluate the complete XPath with attribute filters. I did use XPathAPI a while ago, so you mite find that there might be updates on the code. Here is a sample code,

String xslt = //your xslt string ..../stream
DocumentBuilderFactory dfactory = DocumentBuilderFactory.newInstance();
dfactory.setValidating(false);
Document d = dfactory.newDocumentBuilder().parse(input);
..you got the org.w3c.dom.Document now...

XPathAPI.selectSingleNode(d, "/stylesheet/template/call-template")

The above will give you the node from there you can say node.getAttribute() and do an assert.

1) The last i used this API it does not support namespaces ("stylesheet" and not "xsl:stylesheet") and also i am not sure if it does any attribute matching... (you can try though)

2) The above is using org.apache.xpath.XPathAPI however i suggest you to try Dom4J also once. I think xpath matching is slightly better there

DizzyDiz

ASKER

Thanks Kannan,

I found a workaround to my problem thanks to a third party API and it's sole author. (Juxy/Pavel Sher) There's two issues with my example I believe. The first issue involves allowing the XPath engine to select based on Namespaces. The second issue (which may have led to my errors, though I'm not sure) is setting the DOM to be namespace aware. That second issues was pointed out to me by Pavel. I also had another issue in code that I did not post involving multiple prefixes pointing to the same namespace. It turns out that that's not a particularly good idea when working with XPath. I fixed that issue and used my work around and now all is well. I actually believe that setting the Document to be namespace aware was causing the majority of my problems. I don't have time to double back and test for this. However if anyone else wishes to comment I'd appreciate the additional insight.

Cliff

ASKER CERTIFIED SOLUTION

Computer101

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