Java Threads, 3rd Edition

Chapter 1. Introduction to Threads

This is a book about using threads in the Java programming language and the Java virtual machine. The topic of threads is very important in Java—so important that many features of the threading system are built into the Java language itself while other features of the threading system are required by the Java virtual machine. Threading is an integral part of using Java.

The concept of threads is not a new one: for some time, many operating systems have had libraries that provide the C programmer a mechanism to create threads. Other languages, such as Ada, have support for threads embedded into the language, much as support for threads is built into the Java language. Nonetheless, until Java came along, the topic of threads was usually considered a peripheral programming topic, one that was only needed in special programming cases.

With Java, things are different: it is impossible to write any but the simplest Java program without introducing the topic of threads. And the popularity of Java ensures that many developers, who might never have considered learning about threading possibilities in a language such as C or C++, need to become fluent in threaded programming.

Futhermore, the Java platform has matured throughout the years. In Java 2 Standard Edition Version 5.0 (J2SE 5.0), the classes available for thread-related programming rival many professional threading packages, mitigating the need to use any commercial library (as was somewhat common ...