DO NOT REPLY [Bug 9731] New: - NullPointerException if non-existent node passed to extension function

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http://nagoya.apache.org/bugzilla/show_bug.cgi?id=9731

NullPointerException if non-existent node passed to extension function

           Summary: NullPointerException if non-existent node passed to
                    extension function
           Product: XalanJ2
           Version: 2.3
          Platform: Other
        OS/Version: Other
            Status: NEW
          Severity: Normal
          Priority: Other
         Component: org.apache.xalan.extensions
        AssignedTo: [EMAIL PROTECTED]
        ReportedBy: [EMAIL PROTECTED]


If an extension function exists which takes a Node parameter, and an xslt tag
specifies as a parameter a path to a node that does not exist, then a
NullPointerException is thrown *before* the extension function is invoked.

I would have expected null to be passed as the node instead.

Note that if the extension function takes a String instead, an empty string is
passed to the extension function in place of the invalid node.

eg 

<?xml version="1.0"?>
<xsl:stylesheet 
  xmlns:xsl="http://www.w3c.org/1999/XSL/Transform";
  xmlns:ecn="xalan://nz.co.ecnetwork.xsltmap">

<xsl:template match="/">
  <xsl:value-of select="ecn:Extensions.doIt(nosuchnode)"/>
</xsl:template>

package nz.co.ecnetwork.xsltmap;
public class Extensions
{
  public static String doIt(Node node)
  {
    System.err.println("this never gets called if node doesn't exist");
  }
}


platform details:
* sun java 1.4.0 on linux
* xalan-j 2.3.1 (using java.endorsed.dirs to override rt.jar)
* default xml parser


**** Any suggestions for workarounds for this problem welcome!!!!