Akka 2.3.0 Major Release
Typesafe is proud to announce the release of Akka 2.3.0, the first step of the Rollins milestone (named after Sonny Rollins whose picture you can see below).
The key features of this release are:
This module allows you to write actors with persistent state that survives hardware and software failures, and it also provides an opt-in mechanism for upgrading actor message sending to at-least-once delivery semantics. The former Eventsourced add-on was ported into the Akka project by Martin Krasser. While the working principle of persisting messages (representing commands or changes to the actor state) to an append-only journal has been retained, there have been numerous improvements in the API and implementation.
Java 8 Support
Akka is prepared for the upcoming release of JDK 8, in particular its most awaited feature: lambda expressions. You can use them to implement Actors and Finite State Machines in a fluent fashion—enjoying a pattern match builder or behavior changes using “become()” without having to declare anonymous inner classes.
We have learned several things from running Akka on 2400 nodes, leading to several performance improvements and usability enhancements. The main change is that with this version a cluster can heal back from being partially “unreachable”: when the affected nodes become responsive again, the failure condition is cleared and everything continues normally. A configurable timeout after which unresponsive nodes are removed from the cluster takes care of fatally failed machines.
In order to get you started with these new features in no time, several Activator templates await your exploration:
- akka-sample-fsm-java-lambda (using Java 8 lambdas)
Thanks to the Community
For this release we had the help of 44 committers, a huge “Thank you!” goes to:
Eugene Platonov, Marcus Ljungblad, Eugene Vigdorchik, Dario Rexin, Levi Notik, Eric Pederson, Marius Seritan, Mark "Justin" Waks, Gastón M. Tonietti, Bryan Hunt, Taylor Leese, Rob David, Adam Voss, oakwhiz, Francois Armand, Nabeel Ali Memon, Michael Pollmeier, Ben McCann, Tomasz Nurkiewicz, Akara Sucharitakul, Konrad Malawski, Dan Hopkins, Luc Perkins, Gaetan Hervouet, Joa Ebert, Andrey Stepachev, Gustav Åkesson, Sander Mak, Paulo Siqueira, Ian Wormsbecker, Daniel Hobi, Przemyslaw Piotrowski (Typesafe personnel excluded).
For the full details please check out the release announcement on the Akka site.