The Java language was developed at Sun Microsystems in 1991 as part of a research project to develop software for consumer electronics devices—television sets, VCRs, toasters, and the other sorts of machines you can buy at any department store. Java’s goals at that time were to be small, fast, efficient, and easily portable to a wide range of hardware devices. It is those same goals that made Java an ideal language for distributing executable programs via the World Wide Web, and also a general-purpose programming language for developing programs that are easily usable and portable across different platforms.
The Java language was used in several projects within Sun, but did not get very much commercial attention until it was paired with Hot At the time this book is being written, Sun has released the beta version of the Java Developer’s Kit (JDK), which includes tools for developing Java applets and applications on Sun systems running Solaris 2.3 or higher for Windows NT and for Windows 95. By the time you read this, support for Java development may have appeared on other platforms, either from Sun or from third-party companies.Java. Hot Java was written in 1994 in a matter of months, both as a vehicle for downloading and running applets and also as an example of the sort of complex application that can be written in Java.
Support for playing Java programs is a little more confusing at the moment. Sun’s HotJava is not currently included with the Beta JDK; the only available version of HotJava is an older alpha version, and, tragically, applets written for the alpha version of Java do not work with the beta JDK, and vice versa. By the time you read this, Sun may have released a newer version of HotJava which will enable you to view applets.
The JDK does include an application called appletviewer that allows you to test your Java applets as you write them. If an applet works in the appletviewer, it should work with any Java-capable browser. You’ll learn more about applet viewer later today.
What’s in store for the future? In addition to the final Java release from Sun, other companies have announced support for Java in their own World Wide Web browsers. Netscape Communications Corporation has already incorporated Java capabilities into the 2.0 version of their very popular Netscape Navigator Web browser—pages with embedded Java applets can be viewed and played with Netscape. With support for Java available in as popular a browser as Netscape, tools to help develop Java applications (debuggers, development environments, and so on) most likely will be rapidly available as well.