68 The XML Files: Develo pment of XML/XSL A pplications Using WebSp here Studio
Stylesheet compilation
Before a stylesheet can be processed, it must be converted i nto some internal
machine readable format. Usually the stylesheet is read into memory using an
XML parser, translated into machine format and then preserved in memory for
repeated use. This is called stylesheet compilation.
Different XSLT processors implement stylesheet compilation differently, so JAXP
includes the javax.xml.transform.Templates interface to provide consistency.
The newTransformer() method of this interface is widely used. It allows you to
obtain a new instance of a class that implements the Transformer interface. It is
this Transformer object that actually allows you to perform XSLT transformations.
Since the implementation of the Templates interface is hidden by JAXP, it must be
created by the following method on javax.xml.transform.TransformerFactory:
public Template newTemplates(Source source) throws
TransformeConfigurationException
As mentioned earlier, the Source may obtain the XSLT stylesheet from one of
many locations, including a filename, a system identifier, or even a DOM tree.
Regardless of the original location, the XSLT processor is supposed to compile
the stylesheet into an optimized internal representation.