how to call external java function in xslt file?

问题:

I have this xslt file that I need to call a java function placed somewhere else in the same application. In the xslt file I have

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" 
                xmlns:java="java" 
                xmlns:test_my="vobs.plugins.WikiParser.WikiParser"
                version="2.0">
  <xsl:output indent="yes" method="html"/>
  <xsl:template match="/">
    <H1>
      <xsl:value-of select="WikiDescription/Title"/>
    </H1>
    Summary: <xsl:value-of select="WikiDescription/Description"/>
    <xsl:variable name="text">                      
      <xsl:value-of select="WikiDescription/Text"/>
    </xsl:variable>
    <p>
      <xsl:value-of select="test_my:parse2($text)" 
                    disable-output-escaping="yes"/>
    </p>

but when I try to excute this xlst file I got the following error

XSL transform reported error: 
XPath syntax error at char 21 on line -1 in {test_my:parse2($text)}: 
Cannot find a matching 1-argument function named 
{vobs.plugins.WikiParser.WikiParser}parse2()

it seems like that it couldn't find the java class, so what's the right way to do this? some code example will be even better. Thanks in advance!

回答1:

It depends on what XSLT transformation processor you are using. Saxon uses urn:java:; Xalan uses xalan://.

回答2:

I had exactly the same problem and this solved it for me where urn:java: and java: both failed.

Assuming you're using Xalan to do the transformation, you should change xmlns:test_my="vobs.plugins.WikiParser.WikiParser" to xmlns:test_my="xalan://vobs.plugins.WikiParser.WikiParser".

回答3:

You need to change the namespace declaration (at the xsl:stylesheet element) from xmlns:test_my="vobs.plugins.WikiParser.WikiParser" to xmlns:test_my="urn:java:vobs.plugins.WikiParser.WikiParser"

The rationale is as follows: In order to use a class C from package a.b you need to define a namespace prefix and associate it with the urn:java:a.b.C.

If I understand XSL correctly the urn: prefix is needed when importing Java code that is not part of the standard library (as in your case). If you only need to import standard library classes then "java:" will do.

(Further details: http://cafeconleche.org/books/xmljava/chapters/ch17s03.html)

[EDIT: change "java:" -> "urn:java:"]