Introduction to akka actors with java 8
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Akka is a toolkit for building highly concurrent, distributed, and resilient message-driven applications on the JVM. It uses the actor model where actors receive messages asynchronously and respond by sending messages, changing their state, or spawning new actors. Actors can be organized hierarchically and monitor each other. The toolkit also includes tools for clustering actors across nodes and building asynchronous data streams.
Introduction to akka actors with java 8
- 1. Introduction to Akka Actors with Java 8
- 3. Instead of more Ghz more cores source: http://queue.acm.org/detail.cfm?id=2181798
- 4. Another thing that has changed
- 5. Build powerful concurrent & distributed applications more easily. Akka is a toolkit and runtime for building highly concurrent, distributed, and resilient message-driven applications on the JVM
- 6. ”The actor model in computer science is a mathematical model of concurrent computation that treats actors as the universal primitives of concurrent computation. ” Wikipedia The Actor Model
- 7. An Actor and acts on them by: • Sending messages • Changing its state • Changing its behavior • Creating more actors receives messages
- 8. The Actor hierarchy /user system.actorOf(props, ”my-actor”) /user/my-actor getContext() .actorOf(…, ”my-child”) /user/my-actor/my-child
- 11. Dispatch (Actor Execution) Actor-a Actor-b Thread 1 Thread 2 b b ba a a Time
- 12. Blocking Actor-a Actor-b Thread 1 Thread 2 b b a Time a Actor-c
- 13. Dos and don’ts Don’t: Put every actor under /user Separate parts using supervisors so they can fail independently Do: Isolate blocking Put blocking logic on its own thread based dispatcher Don’t: Write all your logic inside your actors Make what is possible ”regular” OO logic that you can set up and unit test synchronously Do: Make all messages immutable Or else there will be concurrency/visibility problems Do: Put asynchronous boundaries where it makes sense Three tier where each tier is an actor is probably not that useful
- 14. What more is there? Akka Cluster Akka Streams and cluster tools async & back-pressured
- 15. Get started Learn more - the docs: http://akka.io/docs Get help: gitter channel: https://gitter.im/akka/akka mailing list: https://groups.google.com/forum/#!forum/akka-user Project with samples: https://github.com/johanandren/akka-actor-java8-webinar