future.scala

import org.joda.time.DateTime

import scala.concurrent.ExecutionContext.Implicits.global
import scala.concurrent.{Await, ExecutionContext, Future}
import scala.concurrent.duration._


object FooBar {

  def slowThing(number: Int)(implicit ec: ExecutionContext): Future[Unit] = {

    println(s"${new DateTime().toString()}: Pre future for $number ")

    val res = Future {

      println(s"${new DateTime().toString()}: Start of future for $number ")


      Thread.sleep(10 * 1000)

      println(s"${new DateTime().toString()}: End of future for $number ")

    }

    println(s"${new DateTime().toString()}: Post future for $number ")


    res
  }

  def main(args: Array[String]): Unit = {

    val agg = for (u1 <- slowThing(1);
                   u2 <- slowThing(2)) yield (u1, u2)

  
    println("Waiting for 25")
    Thread.sleep(25 * 1000)
    println("Done waiting")


  }
  
  
2015-07-21T16:28:10.078-04:00: Pre future for 1 
2015-07-21T16:28:10.168-04:00: Post future for 1 
2015-07-21T16:28:10.168-04:00: Start of future for 1 
Waiting for 25
2015-07-21T16:28:20.169-04:00: End of future for 1 
2015-07-21T16:28:20.169-04:00: Pre future for 2 
2015-07-21T16:28:20.169-04:00: Post future for 2 
2015-07-21T16:28:20.170-04:00: Start of future for 2 
2015-07-21T16:28:30.170-04:00: End of future for 2 
2015-07-21T16:28:30.170-04:00: All Done!!!!
Done waiting