The Extensible Stylesheet Language Transformations APIs

Figure 4-3 shows the XSLT APIs in action.

XSLT APIs: A TransformerFactory creates a Transform object,which followsTransformation Instructions to convert a Source data setinto a Result data set.

Figure 4-3 XSLT APIs

A TransformerFactory object is instantiated and used to create a Transformer. The source object is the input to the transformation process. A source object can be created from a SAX reader, from a DOM, or from an input stream.

Similarly, the result object is the result of the transformation process. That object can be a SAX event handler, a DOM, or an output stream.

When the transformer is created, it can be created from a set of transformation instructions, in which case the specified transformations are carried out. If it is created without any specific instructions, then the transformer object simply copies the source to the result.

The XSLT Packages

The XSLT APIs are defined in the packages shown in Table 4-3.

Table 4-3 XSLT Packages
Package
Description
javax.xml.transform
Defines the TransformerFactory and Transformer classes, which you use to get an object capable of doing transformations. After creating a transformer object, you invoke its transform() method, providing it with an input (source) and output (result).
javax.xml.transform.dom
Classes to create input (source) and output (result) objects from a DOM.
javax.xml.transform.sax
Classes to create input (source) objects from a SAX parser and output (result) objects from a SAX event handler.
javax.xml.transform.stream
Classes to create input (source) objects and output (result) objects from an I/O stream.