Does a future implemented like below get a new thread? Apparently it is not(see the output below). Why? What should I do if I want my code to run on a new thread?
package MyTest
import com.twitter.util._
import scala.language.postfixOps
object Test {
def test1 = Future {
println("BeforeTest", Thread.currentThread())
Thread.sleep(5000)
println("AfterTest", Thread.currentThread())
}
def test2 = test1 onSuccess { case _ => println("Future on success") }
def main(args: Array[String]): Unit = {
println("main", Thread.currentThread())
test2
println("main123", Thread.currentThread())
}
}
Output:
(main,Thread[run-main-0,5,run-main-group-0])
(BeforeTest,Thread[run-main-0,5,run-main-group-0])
(AfterTest,Thread[run-main-0,5,run-main-group-0])
Future on success
(main123,Thread[run-main-0,5,run-main-group-0])
You are using twitter futures, not scala futures. Twitter futures are not multithreaded by default. You have to use a FuturePool (passing it an ExecutorService with your threadpool of choice)
Non-tested example (simple enough to work I hope :) ):
val executor = Executors.newFixedThreadPool(4)
val pool = FuturePool(executor)
def test1 = pool {
println("BeforeTest", Thread.currentThread())
Thread.sleep(5000)
println("AfterTest", Thread.currentThread())
}
def test2 = test1 onSuccess { case _ => println("Future on success") }
def main(args: Array[String]): Unit = {
println("main", Thread.currentThread())
test2
println("main123", Thread.currentThread())
executor.shutdown()
}