Conditional statements in XSLT

Hi all,

I'm using Xalan J XSLT processor, version 2.7.0, and though I don't have a
particular problem with the implementation of Xalan I'm having trouble
implementing one of the requirements for our project,  I'm even not sure if is
at all possible to do it applying only XSL transformations.
Can anyone advise me on this one?
******* Problem Description: ***********
I have the following input xml document:
<RESULT>
  <PARAMETERS>
    <CYCLE>
      <ENDDATE>20060215</ENDDATE>
    </CYCLE>
    <FILE><CHECK/></FILE>
  </PARAMETERS>
  <OUTPUT>
    <FILE>b</FILE>
    <FILENAME>E:\ftphome\vodafone\xml\CC20060215S50.XML</FILENAME>
  </OUTPUT>
</RESULT>

Now, the resulting xml should have the FILE and FILENAME tags belonging to
OUTPUT element transferred to PARAMETERS element, which I can do with no
effort at all with the following template:
<--! Coy input node to the output -->
<xsl:template match="*">
       <xsl:copy>
       <xsl:apply-templates />
</xsl:copy>
</xsl:template>
<xsl:template match="OUTPUT"></xsl:template> <!--Output node is not copied to
output -->
<--! Copy output nodes to Parameters element -->
<xsl:template match="/RESULT/PARAMETERS">
       <xsl:copy>
       <xsl:copy-of select="/RESULT/OUTPUT/*" />
       <xsl:apply-templates />
       <xsl:copy>
</xsl:template>

The tricky thing here is that if the FILE/FILENAME tag (or any tag under
OUTPUT) exists under PARAMETERS, then the tag under PARAMETERS should be
overwritten by correspondent OUTPUT tag. In this case the correct output
should be the following:
<RESULT>
  <PARAMETERS>
    <CYCLE>
      <ENDDATE>20060215</ENDDATE>
    </CYCLE>
   <FILE>b</FILE>
   <FILENAME>E:\ftphome\vodafone\xml\CC20060215S50.XML</FILENAME>
  </PARAMETERS>
</RESULT>

I would much appreciate some help,.

Many many thanks
Higino Silva



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