The XML Resource Model

The XML resource model supports the information type XML.

The Extensible Markup Language (XML) resource model is based on the XML information exchange standard. The XML resource model is useful for applications that exchange information across organizational boundaries, request or process XML based messages or generally need a powerful information model which supports tree-structured information.

The XML world is rich and growing. Technologies such as XQuery providing the ability to use SQL-like queries against information stored as XML. XSLT provides the ability to transform one XML document into another using a declarative transformation rule set. XSL-FO will transform XML into page-layout format suitable for conversion to PDF, Postscript or other page-layout languages.

The XML family of technologies is rich and varied. In this section we introduce the major technologies also offer a growing set of tutorials.

Services and Functions

The primary services include:

Service	Descriptions
active:xquery	Executes an XQuery script.
active:xslfo‑fop	Renders flow objects information into one of several formats (PDF, SVG, PCL, AWT, print, text, MIF, XML).
active:xslt	XSL Stylesheet transformations
active:xslt2	XSL Stylesheet transformations based on the XSLT 2.0 specification.

Physical Representations

There are several popular physical representations of XML, each with different tradeoffs. Because NetKernel supports a logical view of XML one can develop applications without worrying about the detail of the representation model. NetKernel transreptors convert between the different representations transparently.

The two major categories are event-driven (SAX) style and in-memory (DOM) style representations. NetKernel supports DOM, SAX, DOMXDA (a semi-declarative API representation of XML developed by 1060 Research), XMLBeans, JDOM and STAX. Others can be added at any time by supplying suitable transreptors and supporting services.

Transrepresentations

XML transreptors are provided between many of the supplied representations. In addition transreptor pipelining ensures all XML representations can be seamlessly interchanged.