The world is changing: Multiprocessor systems have gone from being rare and expensive to being ubiquitous. A four-CPU system used to qualify as a big, multiway system--now even inexpensive desktops have four CPU cores.

As the hardware reality changes, so do the programs we want to write and so must the platform and libraries we rely on. The java.util.concurrent package, introduced on the JavaT Platform, Standard Edition 5 (Java SE 5 platform), was a huge step forward, making coarse-grained concurrency much easier. But as processor counts continue to increase, developers are looking for finer-grained concurrency so that they can effectively exploit today's hardware.

On the Java SE 7 platform, the java.util.concurent package will grow to address the need to exploit finer-grained concurrency, in the form of the fork-join framework. Fork-join is a technique for parallel decomposition that has been used in the parallel programming community for many years but that is starting to become relevant for accelerating concurrent applications.

This presentation looks at the fork-join package, how it works, and how to use it, as well as other concurrency improvements on the Java SE 7 platform.