STM 重试直到依赖得到满足或超时

package STM
import scala.concurrent.stm.Ref
import scala.concurrent.stm.atomic
import scala.concurrent.stm.retry
import scala.concurrent.stm.retryFor
import java.util.Timer
import java.util.TimerTask
import java.util.concurrent.TimeUnit

object SensibleWait {

  val start = System.nanoTime()

  val cups = Ref(24)

  def fillCup(numberOfCups: Int) = {

    atomic {
      implicit tx =>
        {
          if (cups() < numberOfCups) {
            println("retry........ at " + (System.nanoTime() - start) / 1.0e9)
            retryFor(5, TimeUnit.SECONDS)
          }
          cups.swap(cups() - numberOfCups)
          println("Fill up ... " + numberOfCups)
          println("........ at " + (System.nanoTime() - start)/1.0e9)
        }
    }
  }

  def main(args : Array[String]) = {
    val timer = new Timer(true)
    
    timer.schedule(new TimerTask() {
      def run() {
        println("Refilling.... at " + (System.nanoTime() - start)/1.0e9)
        atomic {
          implicit tx => cups() = 24
        }
      }
    }, 5000)
    
    SensibleWait.fillCup(20)
    SensibleWait.fillCup(10)
    try {
      SensibleWait.fillCup(22)
    } catch {
      case ex : Throwable => println("Failed: " + ex.getMessage())
    }
    println("Ending.....")
  }
 
}