Now you've explored the basic foundations of the Mac OS X Java platform. The next few chapters cover different aspects of Java development, from IDEs and tools, rich desktop application GUIs, and application packaging to Apple-specific technologies such as QuickTime and the Speech Framework.
If you are interested in desktop (also known as client-side) development, start with Chapter 4 and Chapter 5, which cover GUI applications and Apple extensions. From there, you may want to move on to standalone applications in Chapter 7. Then you might benefit from exploring other Apple technologies, such as Speech, QuickTime, and Spelling.
There is also a lot to be said about Mac OS X's enterprise support for Java. If you are primarily interested in web-delivered client applications, look at Chapter 8. If you want to learn more about web application development, concentrate on Chapter 12 through Chapter 15.
No matter what sort of application you're building, if maintaining cross-platform compatibility is important, be sure to review the material in Chapter 6.