Scala future error recovery/handling

gistfile1.txt

object TMP extends App {
  import scala.concurrent.{Future, Await}
  import scala.concurrent.ExecutionContext.Implicits.global
  import scala.concurrent.duration._

  def b1 = {
    val f: Future[Int] = scala.concurrent.future { 100 }
    val r = Await.result(f, 1.second)
    println(":> " + r)
  }

  def b2 = {
    val f: Future[Int] = scala.concurrent.future { throw new Exception("Borken") }
    val r = Await.result(f, 1.second)
    println(":> " + r)
  }

  def b3 = {
    val f: Future[Int] = scala.concurrent.future { throw new Exception("Borken") } recover { case e => println(":< " + e); 0 }
    val r = Await.result(f, 1.second)
    println(":> " + r)
  }

  def b4 = {
    val f: Future[Int] = scala.concurrent.future { throw new Exception("Borken") } recover { case e => throw new Exception("Couldn't get the int", e) }
    val r = Await.result(f, 1.second)
    println(":> " + r)
  }

  def b5 = {
    val f: Future[Int] = scala.concurrent.future { if (math.random < .5) 76 else throw new Exception("Bork") } map (_ / 2) recover { case e => throw new Exception("Couldn't get the int", e) }
    val r = Await.result(f, 1.second)
    println(":> " + r)
  }

  b5

}