Reactivity @ JavaLand 2014

Transcript

1. REACTIVITY NIKO KÖBLER HEIKO SPINDLER QUALITECTS GROUP
2. Reactivity?  Reaktive Manifesto www.reactivemanifesto.org  The 100% perfect world  Can only be a guide
3. Reactivity? event driven responsive scalable resiliant
4. Known concepts  Enterprise-Architecture:  JMS  CEP  SOA  Handle technical challenges  Concepts finding their way into applications / programming level
5. JavaScript – Meteor Java – Akka DEMO
6. Meteor  http://www.meteor.com  JavaScript fullstack reactive plattform (DB, server, UI)  Features  One language  Send data, not HTML  Database everywhere  Data synchronisation  Latency compensation
7. Akka  http://akka.io  Implementation of the actor-model with Scala and Java  Features  Actors exchange asynchronuous messages  Loose coupling  Actors are lightweight  Distribution  Error handling
8. ActorSystem ActorRef Message Dispatcher Mailbox Actor MessageQueue Create Dispatch Runs Invoke Publish Messages Get Messages
10. Changed Requirements Requirement past today Response time sec  ms Server count 1 – 10  100 – 1000 Downtime hours  n/a Data volume GB  TB
11. Advantages of Reactivity  Divide and conquer  Separation of Concerns  More options to design applications  Frameworks support and may reduce work
12. Frameworks  Node.js  Vert.x  Akka  Play  Reactor  Meteor  react.js  ... BUT: A framework alone does not make you reactive!!
13. Amdahls Law The speedup of a program using multiple processors in parallel computing is limited by the sequential fraction of the program. For example, if 95% of the program can be parallelized, the theoretical maximum speedup using parallel computing would be 20× as shown in the diagram, no matter how many processors are used. (from: Wikipedia/Reactive Manifesto)
14. Challenges  Asynchronuous / non-blocking characteristics  More intellectual effort (initially)  because it‘s „new“  contradicts our used-to, imperative programming  No state  Data distribution
15. Challenges  More effort in architecture considerations  Impulse for reactivity is based on the domain requirements  Exceed (known) complexity borders  Not necessarily suitable for small projects
16. Testing  Simple or complex? Simple AND complex!
17. Q & A NIKO KÖBLER – @dasniko HEIKO SPINDLER – @brainbrix QUALITECTS GROUP – www.qualitects-group.com REACTIVITY