Java and XML

Chapter 14. XML Schema

As a final look at XML, and, in particular, XML topics that are particularly hot right now, we’ll spend a bit of time discussing XML Schema. Although the last several chapters have focused specifically on using Java to manipulate XML, in this chapter we look at XML Schema as a whole. In fact, XML Schema is still relatively new and the support for specific Java classes and interfaces to manipulate XML Schema has been slow in surfacing.

Despite the difficulty in using XML Schema directly through Java, the specification for XML Schema is important enough to warrant further discussion. In this chapter, we first spend time discussing whether using XML Schema is a stable and good choice, particularly as compared to continuing to use DTDs. We then spend a bit of time discussing how XML Schema closely maps to Java, and how that relationship may cause some significant changes to the way XML content is stored.

To DTD or Not To DTD

Although nearly every XML content author and developer has been hearing about XML Schema for almost a year, there is still quite a bit of uncertainty as to whether XML Schema is ready to be used in “prime time.” While some of this concern is based on the changes and immaturity of the XML Schema specification, the majority seems to be based on a familiarity with DTDs. Many XML developers still use only DTDs for document constraints, despite the wave of publicity that XML Schema has received. There are quite a few reasons for this resistance ...