Utility Classes for Concurrent Java Programminghttp://gee.cs.oswego.edu/dl/classes/EDU/oswego/cs/dl/util/concurrent/
This package provides standardized, efficient versions of utility
classes commonly encountered in concurrent Java programming. This code
consists of implementations of ideas that have been around for ages and
is merely intended to save you the trouble of coding them. Discussions
of the rationale and application of several of these classes can be
found in the second edition of Concurrent Programming in Java.