2.1 Upgrading Your AWT Programs

One of the benefits of object-oriented languages is that you can upgrade pieces of a program without rewriting the rest. While practice is never as simple as theory, with Swing it's close. You can use most of the Swing components as drop-in replacements for AWT components with ease. The components sport many fancy new features worth exploiting, but they still maintain the functionality of the AWT components you're familiar with. As a general rule, you can stick a "J" in front of your favorite AWT component and put the new class to work as a Swing component. Constructors for components such as JButton, JTextField, and JList can be used with the same arguments and generate the same events as Button, TextField, and List. Some Swing containers, like JFrame, take a bit of extra work, but not much.

Graphical buttons are essential to modern user interfaces. Nice monitors and cheap hardware have made icons almost a necessity. The AWT package in Java does not directly support image buttons. You could write an extension to support them easily enough, but why bother when Swing's JButton class provides a standard way to add image buttons?