XML is fundamentally about data; programming with XML, then, has to be fundamentally about getting at that data. That process, called parsing, is the basic task of the APIs I’ll cover in the next several chapters. This chapter describes how an XML document is parsed, focusing on the events that occur within this process. These events are important, as they are all points where application-specific code can be inserted and data manipulation can occur.
I’m also going to introduce you to one of the two core XML APIs in Java: SAX, the Simple API for XML (http://www.saxproject.org). SAX is what makes insertion of this application-specific code into events possible. The interfaces provided in the SAX package are an important part of any programmer’s toolkit for handling XML. Even though the SAX classes are small and few in number, they provide a critical framework for Java and XML to operate within. Solid understanding of how they help in accessing XML data is critical to effectively leveraging XML in your Java programs.
For the impatient, the other of those two core APIs is DOM. Coverage of DOM begins in Chapter 5.
I’m increasingly of the “learning is best done by doing” philosophy, so I’m not going to hit you with a bunch of concept and theory before getting to code. SAX is a simple API, so you only need to understand its basic model, and how to get the API on your machine; beyond that, code will be your best teacher.