These are briefly presented here to help developers understand the intended role of this library. The reference implementation of the above packages is currently in the com.sun.xml. A variety of facilities can be built on top of core APIs, but are sufficiently specialized that not all environments supporting XML would require them. A package supporting the transformation parts of XSL could be useful in many environments, including XML document servers. Some services such as WebDAV might use XML internally, and not expose it.
Applications build on the core, often building on higher level services.
Applications may have server side components, client side ones, or both. Web based server side components will often be built using Java Servlets or JavaServer Pages. Optional Package provides basic functionality for reading, manipulating, and generating XML documents through pure Java APIs. Public Draft 1. The Java API for XML Parsing Specification v1.0 has now been released as Public Draft 1.