Sidebar: The Java Development Kit

To develop Java applets, you need the Java development kit. Luckily, you can download this from a number of sites on the Internet. The Solaris and Win95 version can be found at ftp://ftp.java.com. The Java Development Kit (JDK) for other platforms is available through other Internet servers, you can use a search engine such as Yahoo or Lycos to find these. There is also a JDK available for Linux.

After downloading the complete JDK, you end up with a number of directories and files. In the bin directory, you will find these programs :

appletviewer--This program enables you to look at applets without a browser

javac--The Java compiler

java--The Java interpreter

jdb--The Java debugger

In the classes directory, you will find a number of subdirectories that contain class libraries. The most important ones are: awt, which contains the Abstract Windows Toolkit, io which contains the I/O routines, and net which contains the network classes.

But most important of all, the JDK I use, which is bundled with the book Hooked on JAVA, by Van Hoff, Shaio, and Starbuck (Addison-Wesley), also has two subdirectories called demo and src. They contain a lot of demo applets, plus their source and the source for a number of class libraries. I personally find the files in these directories very instructive, and if you want to go further with Java, these will be a good starting point.