Introduction to Java

The Next Stage of the Known,
Or a Completely New Paradigm?

Taiichi Sakaiya--The Knowledge-Value Revolution

The Software Developer's Burden

Imagine you're a software application developer. Your programming language of choice (or the language that's been foisted on you) is C or C++. You've been at this for quite a while and your job doesn't seem to be getting any easier. These past few years you've seen the growth of multiple incompatible hardware architectures, each supporting multiple incompatible operating systems, with each platform operating with one or more incompatible graphical user interfaces. Now you're supposed to cope with all this and make your applications work in a distributed client-server environment. The growth of the Internet, the World-Wide Web, and "electronic commerce" have introduced new dimensions of complexity into the development process.

The tools you use to develop applications don't seem to help you much. You're still coping with the same old problems; the fashionable new object-oriented techniques seem to have added new problems without solving the old ones. You say to yourself and your friends, "There has to be a better way"!

The Better Way is Here Now

Now there is a better way--it's the Java^TM programming language platform ("Java" for short) from Sun Microsystems. Imagine, if you will, this development world...

• Your programming language is object oriented, yet it's still dead simple.
• Your development cycle is much faster because Java is interpreted. The compile-link-load-test-crash-debug cycle is obsolete--now you just compile and run.
• Your applications are portable across multiple platforms. Write your applications once, and you never need to port them--they will run without modification on multiple operating systems and hardware architectures.
• Your applications are robust because the Java run-time system manages memory for you.
• Your interactive graphical applications have high performance because multiple concurrent threads of activity in your application are supported by the multithreading built into the Java language and runtime platform.
• Your applications are adaptable to changing environments because you can dynamically download code modules from anywhere on the network.
• Your end users can trust that your applications are secure, even though they're downloading code from all over the Internet; the Java run-time system has built-in protection against viruses and tampering.

You don't need to dream about these features. They're here now. The Java Programming Language platform provides a portable, interpreted, high-performance, simple, object-oriented programming language and supporting run-time environment. This introductory chapter provides you with a brief look at the main design goals of the Java system; the remainder of this paper examines the features of Java in more detail.

The last chapter of this paper describes the HotJava^TM Browser ("HotJava" for short). HotJava is an innovative World-Wide Web browser, and the first major applications written using the Java platform. HotJava is the first browser to dynamically download and execute Java code fragments from anywhere on the Internet, and can do so in a secure manner.