scala - Adding a graph to a SourceQueue so we can run a endless stream -


i new akka streams library , decided learn example. trying catch keyboard events , pass through endless stream. idea divide stream in 2 separate processing , end them in different sinks.

this short example of event handler have works.

object keylistener extends org.jnativehook.keyboard.nativekeylistener {   implicit val system = actorsystem("key-events-streaming-system")   implicit val materializer = actormaterializer()    val buffersize = 100   //if buffer fills strategy drops oldest elements   //upon arrival of new element.   val overflowstrategy = akka.stream.overflowstrategy.drophead   val queuenativekeyevents = source.queue[nativekeyevent](buffersize, overflowstrategy)                                                                             .filter(event => event.getrawcode > 0)                                                                             .to(sink.foreach(println(_)))                                                                             .run()   def nativekeypressed(event: nativekeyevent): unit = {    queuenativekeyevents.offer(event)    }   def nativekeytyped(event: nativekeyevent): unit = {     system.out.print("test")   }   def nativekeyreleased(event: nativekeyevent): unit = {     system.out.print("test")   } }

now understand want setup each key press event gets added source , travels through stream have setup.

how configure kind of source. when "run" graph have created ?

i think going wrong somewhere fundamental understanding of streams.

appreciate !

update : yes above example works fine , stream run everytime new element enters it. challenge dealing want divide filtered stream graph if takes 1 input , divides 3 streams , processes them in different paths down line. think can create graph takes 1 input , split them in different paths , result in different sinks side effecting work required of each path. cannot wrap head around how add graph source queue ?


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