Java in a Nutshell, 5th Edition

Chapter 16. java.util and Subpackages

This chapter documents the java.util package, and each of its subpackages. Those packages are:

java.util

This package defines many important and commonly used utility classes, the most important of which are the various Collection, Set, List, and Map implementations. In Java 5.0 the collection classes and interfaces have been converted into generic types.

java.util.concurrent

This package includes utilities for concurrent programming, including threadsafe collection classes, threadpool implementations, and synchronizer utilities.

java.util.concurrent.atomic

This package includes classes that define atomic operations on primitive values or object references.

java.util.concurrent.locks

This package contains low-level lock and condition utilities.

java.util.jar

This package defines classes for reading and writing JAR (Java ARchive) files. They are based on the classes of the java.util.zip package.

java.util.logging

This package defines a powerful and flexible logging API for Java applications.

java.util.prefs

This package allows applications to set and query persistent values for user-specific preferences or system-wide configuration parameters.

java.util.regex

This package defines an API for textual pattern matching using regular expressions.

java.util.zip

This package defines classes for reading and writing ZIP files and for compressing and uncompressing data using the “gzip” format.