What’s New for Concurrency in Java SE 8?

Java SE 8 was officially released yesterday (March 18th) and given the fact that Java 7 was released back in 2012, there are definitely lots of updates and new features. These updates include improvements to the Java language itself, Java security, Java tools and more. Although a lot of these updates are interesting and important I am specifically interesting in exploring: What’s new for concurrency?

Based on the release notes the concurrency-related additions are:

• New forEach, search and reduction methods in java.util.concurrent.ConcurrentHashMap
• New accumulator and adder classes for double and long types in the java.util.concurrent.atomic package. According to the release notes, these new classes

“…internally employ contention-reduction techniques that provide huge throughput improvements as compared to Atomic variables.”

• A new StampedLock class in the java.util.concurrent.locks package which allows for writing, reading, and optimistic reading access to shared data
• New methods to support a “common pool” in java.util.concurrent.ForkJoinPool
• A number of new classes and interfaces in java.util.concurrent to support asynchronous tasks and computation as well as completion actions
• The addition of parallel array sorting methods to the java.util.Arrays package (using the Fork/Join framework)

The complete Java SE 8 release notes are available here and complete details on the concurrency enhancements are available here.