Welcome to Java—the world’s most widely used computer programming language. In this
book, you’ll learn object-oriented programming—today’s key programming methodology.
You’ll create and work with many software objects in this text.
Java is the preferred language for meeting many organizations’ enterprise programming
needs. Java has also become the language of choice for implementing Internet-based
applications and software for devices that communicate over a network.
In use today are more than a billion general-purpose computers and billions more
Java-enabled cell phones, smartphones and handheld devices (such as tablet computers).
According to a study by eMarketer, the number of mobile Internet users will reach approximately
134 million by 2013.1 Other studies have projected smartphone sales to surpass
personal computer sales in 20112 and tablet sales to account for over 20% of all personal
computer sales by 2015.3 By 2014, the smartphone applications market is expected to
exceed $40 billion,4 which is creating significant opportunities for programming mobile
Java Editions: SE, EE and ME
Java for Programmers, Second Edition is based on Java Standard Edition 6 (Java SE 6) and
Java SE 7. Java is used in such a broad spectrum of applications that it has two other editions.
The Java Enterprise Edition (Java EE), which we use later in the book, is geared toward developing
large-scale, distributed networking applications and web-based applications.
The Java Micro Edition (Java ME) is geared toward developing applications for
small, memory-constrained devices, such as BlackBerry smartphones. Google’s Android
operating system—used on numerous smartphones, tablets (small, lightweight mobile
computers with touch screens), e-readers and other devices—uses a customized version of
Java not based on Java ME.