xslt

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Module

The xslt or xsltc accessor is exported by the urn:org:ten60:netkernel:ext:xml:ura module. Import this module to gain access to the accessor.

Syntax

URI

active:xslt or xsltc

Argument	Rules	Description
operand	Mandatory	the resource to which xslt transform is applied
operator	Mandatory	the resource containing the xslt transform
param1	Optional	optional parameter document
paramN	Optional	optional parameter document

Example Usage

DPML

<instr>
  <type>xslt</type>
  <operand>foo.xml</operand>
  <operator>bar.xsl</operator>
  <target>this:response</target>
</instr>

NetKernel Foundation API

req=context.createSubRequest("active:xslt or xsltc");
req.addArgument("operand", [resource representation, aspect, or URI] );
req.addArgument("operator", [resource representation, aspect, or URI] );
result=context.issueSubRequest(req);

Purpose

The xslt accessor is used to perform an XSLT transform on the operand document. XSLT is a W3C standard for transforming XML documents.

The operand is the XML resource to be transformed, operator contains the xslt transform document.

All other arguments are passed as parameters into the XSLT. These parameters can be referenced within the XSLT by declaring a top-level <xsl:param> in the XSLT stylesheet, the name of the xsl:param must be the same as the name of the argument. Here's an example stylesheet which simply returns the argument param back as the transform result.

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
  <xsl:param name="param" />
  <xsl:template match="/">
    <xsl:copy-of select="$param" />
  </xsl:template>
</xsl:stylesheet>

Compiled Transforms

The underlying Xalan XSLT accessor supports transform compilation. Compiled transforms can be used by specifying xsltc as the instruction type. Use of compiled transforms can lead to significant performance gains, but may come at the cost of an initial compilation overhead. Your application context will determine whether to use interpreted or compiled transforms.

Transform Caching

All XSLT transformations, both interpreted and compiled, are cached and frequently used transforms will not need to be rebuilt. This transparent caching gives good performance gains.

Example

Pipelined XSLT Transfrom

<idoc>
  <instr>
    <type>xslt</type>
    <operand>foo.idoc</operand>
    <operator>bar.xsl</operator>
    <target>var:var</target>
  </instr>
  <instr>
    <type>xslt</type>
    <operand>var:var</operand>
    <operator>bar2.xsl</operator>
    <target>this:response</target>
  </instr>
</idoc>

An example of performing sequential pipelined xslt transforms. The response of the first transform is put in the variable var. The variable is then used as the operand to a second xslt tansform with the result being sent to the response.