I'm trying to use xsl for the first time, and as with
any first-time attempt, I'm running into problems.

I'm trying to transform an XML document into another
XML document with a slightly different format.  Here's
an example of what the source XML looks like:

- - - - begin source.xml - - - -

<?xml version="1.0" encoding="UTF-8"?>

<result>
 <row>
   <column colname="device" colnum="1">syb0201</column>
   <column colname="physical" colnum="2">/dev/rlv0201</column>
   <column colname="dbname" colnum="3">curric_prod</column>
   <column colname="segname" colnum="4">index</column>
   <column colname="mbytes" colnum="5">500</column>
 </row>
 <row>
   <column colname="device" colnum="1">syb0201</column>
   <column colname="physical" colnum="2">/dev/rlv0201</column>
   <column colname="dbname" colnum="3">reports_prod</column>
   <column colname="segname" colnum="4">system</column>
   <column colname="mbytes" colnum="5">300</column>
 </row>
</result>

- - - - end of source.xml - - - -

(There are many more <row> elements, omitted for this example.

Here's what I want the target to look like:

- - - - target.xml - - - -

<?xml version="1.0" encoding="UTF-8"?>

<result>
 <row>
   <device colnum="1">syb0201</column>
   <physical colnum="2">/dev/rlv0201</column>
   <dbname colnum="3">curric_prod</column>
   <segname colnum="4">index</column>
   <mbytes colnum="5">500</column>
 </row>
 <row>
   <device colnum="1">syb0201</column>
   <physical colnum="2">/dev/rlv0201</column>
   <dbname colnum="3">reports_prod</column>
   <segname colnum="4">system</column>
   <mbytes colnum="5">300</column>
 </row>
</result>

- - - - end of target.xml - - - -

Here's the xsl I tried using:

- - - - begin transform.xsl - - - -

<?xml version="1.0"?>

<xsl:stylesheet version = "1.0"
 xmlns:xsl = "http://www.w3.org/1999/XSL/Transform">

 <xsl:template match = "/">
   <xsl:apply-templates/>
 </xsl:template>

 <xsl:template match = "result">
   <result>
     <xsl:apply-templates/>
   </result>
 </xsl:template>

 <xsl:template match = "row">
   <row>
     <xsl:apply-templates/>
   </row>
 </xsl:template>

 <xsl:template match = "column">
   <xsl:element name = "@colname">
     <xsl:attribute name = "colnum">
       <xsl:value-of select = "@colnum"/>
     </xsl:attribute>

     <xsl:template match = "text()">
       <xsl:value-of select = "."/>
     </xsl:template>
   </xsl:element>
 </xsl:template>
</xsl:stylesheet>

- - - - end transform.xsl - - - -

When I apply the transform, it generates the <result> and <row>
elements just fine, but it doesn't generate the elements for the
columns.  I thought that this:

 <xsl:template match = "column">
   <xsl:element name = "@colname">
     <xsl:attribute name = "colnum">
       <xsl:value-of select = "colnum"/>
     </xsl:attribute>

would match a <column> element in the source, create a new
element in the target where the name of the new element is
the value of the colname attribute, and the colnum attribute
is copied verbatim.  But when I apply the transform, I get
stderr output:

Compiler warnings:
 file:///C:/java/transform.xsl: line 25: You
 cannot call an element '@colname'

And my output file looks like this:

- - - - begin out.xml - - - -

<?xml version="1.0" encoding="UTF-8"?><result>

<row>
syb0201
/dev/rlv0201
curric_prod
index
500
</row>
<row>
syb0201
/dev/rlv0201
reports_prod
system
300
</row>
</result>

- - - - end of out.xml - - - -

So it never creates the structure for the column element
(although it does copy the text inside the element correctly).
I don't understand the error "You cannot call an element
@colname," since as I understand it, this simply selects the
value of the colname attribute (right?).

If anybody more familiar with xsl than I can point me in the
right direction, I'd appreciate it.


Larry Coon
University of California