Introduction to Java

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™ programming language environment
(“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compile-link-load-test-crash-debug cycle is obsolete—now you just compile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 Java environment.
• 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 Environment provides a portable, interpreted, highperformance,
simple, object-oriented programming language and supporting runtime
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.


At the end of this paper you’ll find a chapter that describes the HotJava™
Browser (“HotJava” for short). HotJava is an innovative World-Wide Web
browser, and the first major applications written using the Java environment.
HotJava is the first browser to dynamically download and execute Java code
fragments from anywhere on the Internet, and to so so in a secure manner.