Chapter 1. The Java Foundation Classes

The Java Foundation Classes, or JFC, is a loose collection of standard Java APIs for client-side graphics, graphical user interfaces (GUIs), and related programming tasks. They are foundation classes in the sense that most client-side Java applications are built upon these APIs. This book covers the following APIs:

AWT

Although the most powerful and exciting features of the JFC were introduced in Version 1.2 of the Java 2 platform, the JFC also includes the graphics and GUI features of Java 1.0 and Java 1.1. These features are provided by the Abstract Windowing Toolkit (AWT). The graphics and GUI capabilities of the AWT are rudimentary, and many of them have been superseded by more advanced features in Java 1.2. Nevertheless, the AWT is the bedrock upon which more advanced JFC functionality is built.

In addition, there are certain situations in which you cannot take advantage of the new JFC functionality and must instead rely solely on the AWT. For example, common web browsers do not yet support Swing, so if you are writing applets, you have to use the AWT. Because of this, the graphics and GUI APIs of the AWT are discussed right along with the more powerful APIs introduced in Java 1.2.

Swing

Swing is an advanced GUI toolkit written in pure Java. It is built upon the AWT but provides many new GUI components and useful GUI-related application services. Swing offers a pluggable look-and-feel architecture that allows an application to be trivially configured either to display a platform-independent Java look-and-feel or to mimic the look-and-feel of the native operating system. Swing also includes an accessibility API that enables the use of assistive technologies, such as screen readers or screen magnifiers for the vision impaired. Many features of Swing are based on the pioneering design of the Netscape Internet Foundation Classes.

Swing is a core part of the Java 2 platform. It is also available, however, as an extension to Java 1.1.

Java 2D

Java 2D is the name for the state-of-the-art two-dimensional graphics API introduced in Java 1.2. Java 2D is built upon the AWT, but greatly expands on the graphics capabilities that were available in Java 1.0 and Java 1.1. Java 2D includes support for resolution independence, rotation, scaling and shearing of arbitrary graphics, antialiasing of text and graphics, alpha transparency, color compositing, and the use of the full range of fonts installed on the native system.

Printing

The ability to print text and graphics on a page is almost as important as the ability to draw text and graphics on the screen. Java 1.1 introduced simple printing capabilities as part of the AWT, and Java 1.2 includes a more powerful printing API as part of the JFC. This book describes both printing APIs.

Data transfer

An important feature of many client-side applications is the ability to allow user-directed data transfer within the application and between unrelated applications. There are two commonly used data transfer metaphors: cut-and-paste and drag-and-drop. Java 1.1 defined a basic data transfer framework and provided an API for cut-and-paste. Java 1.2 adds support for data transfer using the drag-and-drop metaphor.

Applets

The applet API allows a client-side program to run as an applet, or mini-application, within a web browser or some other form of applet viewer. Technically, the applet API is not part of the JFC, but it is a crucial piece of the client-side Java programming picture and is included in this book.

The rest of the chapters in Part 1, "Introducing the Java Foundation Classes" describe these APIs in far more detail. Read Chapter 2, "Swing and AWTArchitecture", first. After reading that chapter, you can read the remaining chapters in whatever order you prefer. The goal of each chapter is to introduce an API in enough detail so that you can begin to use it in your programs. While reading a chapter, you may find it helpful to refer to the quick-reference material in Part 2, "API Quick Reference" of this book to find detailed API information on the individual classes you are reading about.