Programming in Java

INTRODUCTION
Java is one of a great many computer programming languages in use today. Since it is a fairly new language,
having been first released in 1994 by Sun Microsystems, its design takes advantage of modern ideas about what
makes a good programming language. Historically, new programming languages have usually taken years to
become popular, but Java enjoyed unprecedented growth in popularity from the very day of its release. In fact, today
Java is by some measures the most popular language for new work (http://www.tiobe.com/tpci.htm).
Many long books have been written teaching Java programming, and it is not our purpose in this chapter
to provide a complete tutorial on Java programming. Instead, we will introduce basic programming structures
and techniques with Java. We hope this exposure to one very good language will help readers to understand
ideas presented in other chapters on topics of software, algorithms, operating systems, etc.
In this chapter we will show small but complete programs you can try out for yourself. If you do not already
have access to a Java compiler and Java Virtual Machine (also called the Java Runtime Environment), you can
quickly download the entire Java package, including excellent documentation, directly from the Sun website
(http://java.sun.com/javase/). For work with this chapter, download the Java Standard Edition Development Kit
(JDK), which also includes the Java Runtime Environment.
It’s also a good idea to download the documentation (called JavaDocs) to your own computer, if you have
the room on your disk. You can get to the same documentation on-line at the Sun website, but your access will
be faster if the files are resident on your own computer.
To write programs in Java, you can use any editor or word processor you like. There are also several
integrated development environments (IDEs) available. At first we recommend you simply use an editor with
which you are already comfortable, for the IDEs have a learning curve of their own for you to deal with, and
our focus here will be on the basics of the language.