[prev in list] [next in list] [prev in thread] [next in thread] 

List:       xalan-j-users
Subject:    RE: Extension function expects extra parameter
From:       "Gary L Peskin" <garyp () firstech ! com>
Date:       2002-04-29 6:14:47
[Download RAW message or body]

Brian --

For some reason, $v is being interpreted as a string in your elementAt
call.  Try inserting a

  <xsl:copy-of select="$v"/>

to see what Xalan thinks the value of $v is.

Gary
-----Original Message-----
From: Brian Grainger [mailto:granam@shaw.ca] 
Sent: Saturday, April 27, 2002 11:52 AM
To: xalan-j-users@xml.apache.org
Subject: Extension function expects extra parameter


Greetings.

Xalan-Java 2.3.1 is throwing an exception during a call to an extension
function. The details from the XSLT stylesheet:

[Namespaces]
  xmlns:xalan="http://xml.apache.org/xalan"
  xmlns:string="java.lang.String"
  xmlns:vector="java.util.Vector"

[Example code]
    <xsl:variable name="v" select="vector:new()"/>

    <xsl:for-each select="descendant::*">
      <!-- Save element name into a variable -->
      <xsl:variable name="descendantNode">
        <xsl:value-of select="name(current())"/>
      </xsl:variable>
      <!-- Attach the variable to a vector -->
      <xsl:value-of select="vector:addElement($v,
string:new($descendantNode))"/>
    </xsl:for-each>
    <xsl:call-template name="writeVectorElements">
      <xsl:with-param name="v" select="$v"/>
      <xsl:with-param name="vectorLimit" select="vector:size($v) - 1"/>
    </xsl:call-template>

  <xsl:template name="writeVectorElements">
    <xsl:param name="v"/>
    <xsl:param name="vectorLimit">0</xsl:param>
    <xsl:param name="vectorCount">0</xsl:param>
    <xsl:if test="$vectorLimit &gt;= 0">
      <!-- Write out the vector -->
      <!-- The next line generate the exception -->
      <xsl:value-of select="vector:elementAt($v, $vectorCount)"/>
      <!-- Recurse -->
      <xsl:call-template name="writeVectorElements">
        <xsl:with-param name="vectorLimit" select="$vectorLimit - 1"/>
        <xsl:with-param name="vectorCount" select="$vectorCount + 1"/>
      </xsl:call-template>
    </xsl:if>
  </xsl:template>

[Exception message]

XSLT Error (javax.xml.transform.TransformerException):
java.lang.NoSuchMethodException:
For extension function, could not find method
java.util.Vector.elementAt([ExpressionContext,] #STRING, #NUMBER).
Checked both static and instance methods.

[Method definition]

elementAt(int index) 
Returns the component at the specified index

[Comment]
The elementAt method expects an integer, and returns a Java object,
which in this case should be a java.lang.String. The wording of the
exception message seems to indicate that Xalan is looking for a method
of the form elementAt(String s, int index) which of course it won't
find.

Any suggestions would be gratefully received.

Regards,
Brian 

[prev in list] [next in list] [prev in thread] [next in thread]