scala.actors.scheduler.DelegatingScheduler.scala Maven / Gradle / Ivy
/* __ *\
** ________ ___ / / ___ Scala API **
** / __/ __// _ | / / / _ | (c) 2005-2009, LAMP/EPFL **
** __\ \/ /__/ __ |/ /__/ __ | http://scala-lang.org/ **
** /____/\___/_/ |_/____/_/ | | **
** |/ **
\* */
package scala.actors
package scheduler
import scala.concurrent.ManagedBlocker
/**
* @author Erik Engbrecht
*/
trait DelegatingScheduler extends IScheduler {
protected def makeNewScheduler(): IScheduler
protected var sched: IScheduler = null
final def impl = synchronized {
if ((sched eq null) || (!sched.isActive))
sched = makeNewScheduler()
sched
}
final def impl_= (scheduler: IScheduler): Unit = synchronized {
//TODO: if there is already a scheduler, should it be shutdown?
sched = scheduler
}
/**
* Always active because it will just make a new scheduler if required
*/
def isActive: Boolean = true
def execute(fun: => Unit) = impl.execute(fun)
def execute(task: Runnable) = impl.execute(task)
override def executeFromActor(task: Runnable) = impl.executeFromActor(task)
def shutdown(): Unit = synchronized {
if (sched ne null) {
sched.shutdown()
sched = null
}
}
def newActor(actor: Reactor) = impl.newActor(actor)
def terminated(actor: Reactor) = impl.terminated(actor)
def onTerminate(actor: Reactor)(f: => Unit) = impl.onTerminate(actor)(f)
override def managedBlock(blocker: ManagedBlocker): Unit =
impl.managedBlock(blocker)
}