Understanding DOM
Even before there was XML, there was the Document Object Model (DOM). The
DOM allows a developer to refer to, retrieve, and change items within an
XML structure, and is essential to working with XML. In this tutorial, you
will learn about the structure of a DOM document. You will also learn how
to use Java to create a document from an XML file, make changes to it, and
retrieve the output.

Understanding SAX
This tutorial examines the use of the Simple API for XML version 2.0, or
SAX 2.0. It is aimed at developers who have an understanding of XML and wish
to learn this lightweight, event-based API for working with XML data. It
assumes that you are familiar with concepts such as well-formedness and the
tag-like nature of an XML document. In this tutorial, you will learn how
to use SAX to retrieve, manipulate, and output XML data.