Munch cave concurrency with glitter

cookie.scala

import scala.actors.Future
import scala.actors.Futures._

class ☁ extends Exception
class Cookie(val id: Int) {}
object Cookie {
  val MAX_COOKIES = 20
  val CONSUMPTION_TIME_MS = 1000
  
  @volatile
  var instanceCount = 0
  val lock = new AnyRef

  def ↑ = new ☁
  def get = {
    var i = 0
    lock.synchronized {
      if (instanceCount >= MAX_COOKIES)
        throw ↑

      instanceCount += 1
      i = instanceCount
    }

    new Cookie(i)
  }
}

object MunchCave {
  def hasCookies: Boolean = (Cookie.instanceCount > 0)
  def wantsCookies: Boolean = (Cookie.instanceCount < Cookie.MAX_COOKIES)

  def ☺ : Future[Boolean] = future {
    try {
      val cookie: Cookie = Cookie.get
      println("%d nomming...".format(cookie.id))
      Thread.sleep(Cookie.CONSUMPTION_TIME_MS)
      true
    }
    catch {
      case e: ☁ => {
        println("No thanks :(")
        Thread.sleep(Cookie.CONSUMPTION_TIME_MS)
        false
      }
    }
    
  }
}

while (MunchCave wantsCookies) {
   MunchCave ☺
}