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Diffstat (limited to 'src/actors/scala/actors/InternalActor.scala')
| -rw-r--r-- | src/actors/scala/actors/InternalActor.scala | 546 |
1 files changed, 0 insertions, 546 deletions
diff --git a/src/actors/scala/actors/InternalActor.scala b/src/actors/scala/actors/InternalActor.scala deleted file mode 100644 index 5045ea56e8..0000000000 --- a/src/actors/scala/actors/InternalActor.scala +++ /dev/null @@ -1,546 +0,0 @@ -/* __ *\ -** ________ ___ / / ___ Scala API ** -** / __/ __// _ | / / / _ | (c) 2005-2013, LAMP/EPFL ** -** __\ \/ /__/ __ |/ /__/ __ | http://scala-lang.org/ ** -** /____/\___/_/ |_/____/_/ | | ** -** |/ ** -\* */ -package scala.actors -import java.util.TimerTask -import scala.util.control.ControlThrowable - -private[actors] object InternalActor { - private[actors] trait Body[a] { - def andThen[b](other: => b): Unit - } -} - -private[actors] trait InternalActor extends AbstractActor with InternalReplyReactor with ActorCanReply with InputChannel[Any] with Serializable { - - /* The following two fields are only used when the actor - * suspends by blocking its underlying thread, for example, - * when waiting in a receive or synchronous send. - */ - @volatile - private[actors] var isSuspended = false - - /* This field is used to communicate the received message from - * the invocation of send to the place where the thread of - * the receiving actor resumes inside receive/receiveWithin. - */ - @volatile - private var received: Option[Any] = None - - protected[actors] override def scheduler: IScheduler = Scheduler - - private[actors] override def startSearch(msg: Any, replyTo: OutputChannel[Any], handler: PartialFunction[Any, Any]) = - if (isSuspended) { - () => - synchronized { - mailbox.append(msg, replyTo) - resumeActor() - } - } else super.startSearch(msg, replyTo, handler) - - // we override this method to check `shouldExit` before suspending - private[actors] override def searchMailbox(startMbox: MQueue[Any], - handler: PartialFunction[Any, Any], - resumeOnSameThread: Boolean) { - var tmpMbox = startMbox - var done = false - while (!done) { - val qel = tmpMbox.extractFirst((msg: Any, replyTo: OutputChannel[Any]) => { - senders = List(replyTo) - handler.isDefinedAt(msg) - }) - if (tmpMbox ne mailbox) - tmpMbox.foreach((m, s) => mailbox.append(m, s)) - if (null eq qel) { - synchronized { - // in mean time new stuff might have arrived - if (!sendBuffer.isEmpty) { - tmpMbox = new MQueue[Any]("Temp") - drainSendBuffer(tmpMbox) - // keep going - } else { - // very important to check for `shouldExit` at this point - // since linked actors might have set it after we checked - // last time (e.g., at the beginning of `react`) - if (shouldExit) exit() - waitingFor = handler - // see Reactor.searchMailbox - throw Actor.suspendException - } - } - } else { - resumeReceiver((qel.msg, qel.session), handler, resumeOnSameThread) - done = true - } - } - } - - private[actors] override def makeReaction(fun: () => Unit, handler: PartialFunction[Any, Any], msg: Any): Runnable = - new ActorTask(this, fun, handler, msg) - - /** See the companion object's `receive` method. */ - def receive[R](f: PartialFunction[Any, R]): R = { - assert(Actor.self(scheduler) == this, "receive from channel belonging to other actor") - - synchronized { - if (shouldExit) exit() // links - drainSendBuffer(mailbox) - } - - var done = false - while (!done) { - val qel = mailbox.extractFirst((m: Any, replyTo: OutputChannel[Any]) => { - senders = replyTo :: senders - val matches = f.isDefinedAt(m) - senders = senders.tail - matches - }) - if (null eq qel) { - synchronized { - // in mean time new stuff might have arrived - if (!sendBuffer.isEmpty) { - drainSendBuffer(mailbox) - // keep going - } else { - waitingFor = f - isSuspended = true - scheduler.managedBlock(blocker) - drainSendBuffer(mailbox) - // keep going - } - } - } else { - received = Some(qel.msg) - senders = qel.session :: senders - done = true - } - } - - val result = f(received.get) - received = None - senders = senders.tail - result - } - - /** See the companion object's `receiveWithin` method. */ - def receiveWithin[R](msec: Long)(f: PartialFunction[Any, R]): R = { - assert(Actor.self(scheduler) == this, "receive from channel belonging to other actor") - - synchronized { - if (shouldExit) exit() // links - drainSendBuffer(mailbox) - } - - // first, remove spurious TIMEOUT message from mailbox if any - mailbox.extractFirst((m: Any, replyTo: OutputChannel[Any]) => m == TIMEOUT) - - val receiveTimeout = () => { - if (f.isDefinedAt(TIMEOUT)) { - received = Some(TIMEOUT) - senders = this :: senders - } else - sys.error("unhandled timeout") - } - - var done = false - while (!done) { - val qel = mailbox.extractFirst((m: Any, replyTo: OutputChannel[Any]) => { - senders = replyTo :: senders - val matches = f.isDefinedAt(m) - senders = senders.tail - matches - }) - if (null eq qel) { - val todo = synchronized { - // in mean time new stuff might have arrived - if (!sendBuffer.isEmpty) { - drainSendBuffer(mailbox) - // keep going - () => {} - } else if (msec == 0L) { - done = true - receiveTimeout - } else { - if (onTimeout.isEmpty) { - if (!f.isDefinedAt(TIMEOUT)) - sys.error("unhandled timeout") - - val thisActor = this - onTimeout = Some(new TimerTask { - def run() { - thisActor.send(TIMEOUT, thisActor) - } - }) - Actor.timer.schedule(onTimeout.get, msec) - } - - // It is possible that !onTimeout.isEmpty, but TIMEOUT is not yet in mailbox - // See SI-4759 - waitingFor = f - received = None - isSuspended = true - scheduler.managedBlock(blocker) - drainSendBuffer(mailbox) - // keep going - () => {} - } - } - todo() - } else { - synchronized { - if (!onTimeout.isEmpty) { - onTimeout.get.cancel() - onTimeout = None - } - } - received = Some(qel.msg) - senders = qel.session :: senders - done = true - } - } - - val result = f(received.get) - received = None - senders = senders.tail - result - } - - /** See the companion object's `react` method. */ - override def react(handler: PartialFunction[Any, Unit]): Nothing = { - synchronized { - if (shouldExit) exit() - } - super.react(handler) - } - - /** See the companion object's `reactWithin` method. */ - override def reactWithin(msec: Long)(handler: PartialFunction[Any, Unit]): Nothing = { - synchronized { - if (shouldExit) exit() - } - super.reactWithin(msec)(handler) - } - - /** Receives the next message from the mailbox */ - def ? : Any = receive { - case x => x - } - - // guarded by lock of this - // never throws SuspendActorControl - private[actors] override def scheduleActor(f: PartialFunction[Any, Any], msg: Any) = - if (f eq null) { - // do nothing (timeout is handled instead) - } else { - val task = new ActorTask(this, null, f, msg) - scheduler executeFromActor task - } - - /* Used for notifying scheduler when blocking inside receive/receiveWithin. */ - private object blocker extends scala.concurrent.ManagedBlocker { - def block() = { - InternalActor.this.suspendActor() - true - } - def isReleasable = - !InternalActor.this.isSuspended - } - - private def suspendActor() = synchronized { - while (isSuspended) { - try { - wait() - } catch { - case _: InterruptedException => - } - } - // links: check if we should exit - if (shouldExit) exit() - } - - private def resumeActor() { - isSuspended = false - notify() - } - - private[actors] override def exiting = synchronized { - _state == Actor.State.Terminated - } - - // guarded by this - private[actors] override def dostart() { - // Reset various flags. - // - // Note that we do *not* reset `trapExit`. The reason is that - // users should be able to set the field in the constructor - // and before `act` is called. - exitReason = 'normal - shouldExit = false - - super.dostart() - } - - override def start(): InternalActor = synchronized { - super.start() - this - } - - /** State of this actor */ - override def getState: Actor.State.Value = synchronized { - if (isSuspended) { - if (onTimeout.isEmpty) - Actor.State.Blocked - else - Actor.State.TimedBlocked - } else - super.getState - } - - // guarded by this - private[actors] var links: List[AbstractActor] = Nil - - /** - * Links <code>self</code> to actor <code>to</code>. - * - * @param to the actor to link to - * @return the parameter actor - */ - def link(to: AbstractActor): AbstractActor = { - assert(Actor.self(scheduler) == this, "link called on actor different from self") - this linkTo to - to linkTo this - to - } - - /** - * Links <code>self</code> to actor <code>to</code>. - * - * @param to the actor to link to - * @return the parameter actor - */ - def link(to: ActorRef): ActorRef = { - this.link(to.localActor) - to - } - - /** - * Unidirectional linking. For migration purposes only - */ - private[actors] def watch(subject: ActorRef): ActorRef = { - assert(Actor.self(scheduler) == this, "link called on actor different from self") - subject.localActor linkTo this - subject - } - - /** - * Unidirectional linking. For migration purposes only - */ - private[actors] def unwatch(subject: ActorRef): ActorRef = { - assert(Actor.self(scheduler) == this, "link called on actor different from self") - subject.localActor unlinkFrom this - subject - } - - /** - * Links <code>self</code> to the actor defined by <code>body</code>. - * - * @param body the body of the actor to link to - * @return the parameter actor - */ - def link(body: => Unit): Actor = { - assert(Actor.self(scheduler) == this, "link called on actor different from self") - val a = new Actor { - def act() = body - override final val scheduler: IScheduler = InternalActor.this.scheduler - } - link(a) - a.start() - a - } - - private[actors] def linkTo(to: AbstractActor) = synchronized { - links = to :: links - } - - /** - * Unlinks <code>self</code> from actor <code>from</code>. - */ - def unlink(from: AbstractActor) { - assert(Actor.self(scheduler) == this, "unlink called on actor different from self") - this unlinkFrom from - from unlinkFrom this - } - - /** - * Unlinks <code>self</code> from actor <code>from</code>. - */ - def unlink(from: ActorRef) { - unlink(from.localActor) - } - - private[actors] def unlinkFrom(from: AbstractActor) = synchronized { - links = links.filterNot(from.==) - } - - @volatile - private[actors] var _trapExit = false - - def trapExit = _trapExit - - def trapExit_=(value: Boolean) = _trapExit = value - - // guarded by this - private var exitReason: AnyRef = 'normal - // guarded by this - private[actors] var shouldExit = false - - /** - * <p> - * Terminates execution of <code>self</code> with the following - * effect on linked actors: - * </p> - * <p> - * For each linked actor <code>a</code> with - * <code>trapExit</code> set to <code>true</code>, send message - * <code>Exit(self, reason)</code> to <code>a</code>. - * </p> - * <p> - * For each linked actor <code>a</code> with - * <code>trapExit</code> set to <code>false</code> (default), - * call <code>a.exit(reason)</code> if - * <code>reason != 'normal</code>. - * </p> - */ - protected[actors] def exit(reason: AnyRef): Nothing = { - synchronized { - exitReason = reason - } - exit() - } - - /** - * Terminates with exit reason <code>'normal</code>. - */ - protected[actors] override def exit(): Nothing = { - val todo = synchronized { - if (!links.isEmpty) - exitLinked() - else - () => {} - } - todo() - super.exit() - } - - // Assume !links.isEmpty - // guarded by this - private[actors] def exitLinked(): () => Unit = { - _state = Actor.State.Terminated - // reset waitingFor, otherwise getState returns Suspended - waitingFor = Reactor.waitingForNone - // remove this from links - val mylinks = links.filterNot(this.==) - // unlink actors - mylinks.foreach(unlinkFrom(_)) - // return closure that locks linked actors - () => { - mylinks.foreach((linked: AbstractActor) => { - linked.synchronized { - if (!linked.exiting) { - linked.unlinkFrom(this) - linked.exit(this, exitReason) - } - } - }) - } - } - - // Assume !links.isEmpty - // guarded by this - private[actors] def exitLinked(reason: AnyRef): () => Unit = { - exitReason = reason - exitLinked() - } - - // Assume !this.exiting - private[actors] def exit(from: AbstractActor, reason: AnyRef) { - if (trapExit) { - this ! Exit(from, reason) - } else if (reason != 'normal) - stop(reason) - } - - /* Requires qualified private, because <code>RemoteActor</code> must - * register a termination handler. - */ - private[actors] def onTerminate(f: => Unit) { - scheduler.onTerminate(this) { f } - } - - - private[actors] def stop(reason: AnyRef): Unit = { - synchronized { - shouldExit = true - exitReason = reason - // resume this Actor in a way that - // causes it to exit - // (because shouldExit == true) - if (isSuspended) - resumeActor() - else if (waitingFor ne Reactor.waitingForNone) { - waitingFor = Reactor.waitingForNone - // it doesn't matter what partial function we are passing here - val task = new ActorTask(this, null, waitingFor, null) - scheduler execute task - /* Here we should not throw a SuspendActorControl, - since the current method is called from an actor that - is in the process of exiting. - - Therefore, the contract for scheduleActor is that - it never throws a SuspendActorControl. - */ - } - } - } -} - -/** - * Used as the timeout pattern in - * <a href="Actor.html#receiveWithin(Long)" target="contentFrame"> - * <code>receiveWithin</code></a> and - * <a href="Actor.html#reactWithin(Long)" target="contentFrame"> - * <code>reactWithin</code></a>. - * - * @example {{{ - * receiveWithin(500) { - * case (x, y) => ... - * case TIMEOUT => ... - * } - * }}} - * - * @author Philipp Haller - */ -@deprecated("Use the akka.actor package instead. For migration from the scala.actors package refer to the Actors Migration Guide.", "2.11.0") -case object TIMEOUT - -/** - * Sent to an actor - * with `trapExit` set to `true` whenever one of its linked actors - * terminates. - * - * @param from the actor that terminated - * @param reason the reason that caused the actor to terminate - */ -@deprecated("Use the akka.actor package instead. For migration from the scala.actors package refer to the Actors Migration Guide.", "2.11.0") -case class Exit(from: AbstractActor, reason: AnyRef) - -/** - * Manages control flow of actor executions. - * - * @author Philipp Haller - */ -private[actors] class SuspendActorControl extends ControlThrowable |