AWT Hierarchy

The Java AWT (Abstract Windowing Toolkit) contains the fundamental classes used for constructing GUIs. The abstract Component class is the base class for the AWT. Many other AWT classes are derived from it. (We will not look at most of these classes).

Here is a diagram that shows how the classes of the AWT and Swing fit together. Look it over to get an overview. Refer back to it occasionally as you read these notes.

Some of the AWT classes derived from Component are Button, Canvas, and Container.

The JComponent class is derived from Container and is one of the base classes of Swing. The JFrame class is derived from the AWT Frame class. It is usually the main container for a GUI application.

The JApplet class is sometimes used for Web applets.