This commit is contained in:
Eugene Vigdorchik 2011-05-03 14:10:00 +04:00
commit 98816b1ae8
128 changed files with 2419 additions and 2399 deletions

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@ -78,7 +78,7 @@ object Chameneos {
var sumMeetings = 0
var numFaded = 0
override def preStart = {
override def preStart() = {
for (i <- 0 until numChameneos) actorOf(new Chameneo(self, colours(i % 3), i))
}

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@ -46,7 +46,7 @@ class RestartStrategySpec extends JUnitSuite {
secondRestartLatch.open
}
override def postStop = {
override def postStop() = {
stopLatch.open
}
})
@ -131,7 +131,7 @@ class RestartStrategySpec extends JUnitSuite {
thirdRestartLatch.open
}
override def postStop = {
override def postStop() = {
if (restartLatch.isOpen) {
secondRestartLatch.open
}
@ -189,7 +189,7 @@ class RestartStrategySpec extends JUnitSuite {
secondRestartLatch.open
}
override def postStop = {
override def postStop() = {
stopLatch.open
}
})
@ -243,7 +243,7 @@ class RestartStrategySpec extends JUnitSuite {
restartLatch.open
}
override def postStop = {
override def postStop() = {
stopLatch.open
}
})

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@ -381,7 +381,7 @@ class SupervisorSpec extends WordSpec with MustMatchers with BeforeAndAfterEach
inits.get must be (3)
supervisor.shutdown
supervisor.shutdown()
}
}
}

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@ -14,7 +14,7 @@ import org.scalatest.matchers.MustMatchers
class Ticket669Spec extends WordSpec with MustMatchers with BeforeAndAfterAll {
import Ticket669Spec._
override def afterAll = Actor.registry.shutdownAll()
override def afterAll() { Actor.registry.shutdownAll() }
"A supervised actor with lifecycle PERMANENT" should {
"be able to reply on failure during preRestart" in {
@ -65,7 +65,7 @@ object Ticket669Spec {
self.reply_?("failure1")
}
override def postStop {
override def postStop() {
self.reply_?("failure2")
}
}

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@ -36,7 +36,7 @@ class DataFlowTest extends Spec with ShouldMatchers with BeforeAndAfterAll {
latch.await(10,TimeUnit.SECONDS) should equal (true)
result.get should equal (42)
List(x,y,z).foreach(_.shutdown)
List(x,y,z).foreach(_.shutdown())
}
it("should be able to sum a sequence of ints") {
@ -67,7 +67,7 @@ class DataFlowTest extends Spec with ShouldMatchers with BeforeAndAfterAll {
latch.await(10,TimeUnit.SECONDS) should equal (true)
result.get should equal (sum(0,ints(0,1000)))
List(x,y,z).foreach(_.shutdown)
List(x,y,z).foreach(_.shutdown())
}
/*
it("should be able to join streams") {
@ -158,7 +158,7 @@ class DataFlowTest extends Spec with ShouldMatchers with BeforeAndAfterAll {
val setV = thread {
v << y
}
List(x,y,z,v) foreach (_.shutdown)
List(x,y,z,v) foreach (_.shutdown())
latch.await(2,TimeUnit.SECONDS) should equal (true)
}*/
}

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@ -14,6 +14,7 @@ import java.util.concurrent.atomic.AtomicLong
import java.util.concurrent. {ConcurrentHashMap, CountDownLatch, TimeUnit}
import akka.actor.dispatch.ActorModelSpec.MessageDispatcherInterceptor
import akka.util.{Duration, Switch}
import org.multiverse.api.latches.StandardLatch
object ActorModelSpec {
@ -110,13 +111,13 @@ object ActorModelSpec {
super.dispatch(invocation)
}
private[akka] abstract override def start {
super.start
private[akka] abstract override def start() {
super.start()
starts.incrementAndGet()
}
private[akka] abstract override def shutdown {
super.shutdown
private[akka] abstract override def shutdown() {
super.shutdown()
stops.incrementAndGet()
}
}
@ -216,6 +217,21 @@ abstract class ActorModelSpec extends JUnitSuite {
msgsProcessed = 0,
restarts = 0
)
val futures = for(i <- 1 to 10) yield Future { i }
await(dispatcher.stops.get == 2)(withinMs = dispatcher.timeoutMs * 5)
assertDispatcher(dispatcher)(starts = 2, stops = 2)
val a2 = newTestActor
a2.start
val futures2 = for(i <- 1 to 10) yield Future { i }
await(dispatcher.starts.get == 3)(withinMs = dispatcher.timeoutMs * 5)
assertDispatcher(dispatcher)(starts = 3, stops = 2)
a2.stop
await(dispatcher.stops.get == 3)(withinMs = dispatcher.timeoutMs * 5)
assertDispatcher(dispatcher)(starts = 3, stops = 3)
}
@Test def dispatcherShouldProcessMessagesOneAtATime {

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@ -62,9 +62,9 @@ class FutureSpec extends JUnitSuite {
val future1 = actor1 !!! "Hello" flatMap ((s: String) => actor2 !!! s)
val future2 = actor1 !!! "Hello" flatMap (actor2 !!! (_: String))
val future3 = actor1 !!! "Hello" flatMap (actor2 !!! (_: Int))
assert(Some(Right("WORLD")) === future1.await.value)
assert(Some(Right("WORLD")) === future2.await.value)
intercept[ClassCastException] { future3.await.resultOrException }
assert((future1.get: Any) === "WORLD")
assert((future2.get: Any) === "WORLD")
intercept[ClassCastException] { future3.get }
actor1.stop()
actor2.stop()
}
@ -74,8 +74,8 @@ class FutureSpec extends JUnitSuite {
val actor2 = actorOf(new Actor { def receive = { case s: String => self reply s.toUpperCase } } ).start()
val future1 = actor1 !!! "Hello" collect { case (s: String) => s } flatMap (actor2 !!! _)
val future2 = actor1 !!! "Hello" collect { case (n: Int) => n } flatMap (actor2 !!! _)
assert(Some(Right("WORLD")) === future1.await.value)
intercept[MatchError] { future2.await.resultOrException }
assert((future1.get: Any) === "WORLD")
intercept[MatchError] { future2.get }
actor1.stop()
actor2.stop()
}
@ -102,8 +102,8 @@ class FutureSpec extends JUnitSuite {
c: String <- actor !!! 7
} yield b + "-" + c
assert(Some(Right("10-14")) === future1.await.value)
intercept[ClassCastException] { future2.await.resultOrException }
assert(future1.get === "10-14")
intercept[ClassCastException] { future2.get }
actor.stop()
}
@ -118,19 +118,64 @@ class FutureSpec extends JUnitSuite {
}).start()
val future1 = for {
a <- actor !!! Req("Hello") collect { case Res(x: Int) => x }
b <- actor !!! Req(a) collect { case Res(x: String) => x }
c <- actor !!! Req(7) collect { case Res(x: String) => x }
Res(a: Int) <- actor !!! Req("Hello")
Res(b: String) <- actor !!! Req(a)
Res(c: String) <- actor !!! Req(7)
} yield b + "-" + c
val future2 = for {
a <- actor !!! Req("Hello") collect { case Res(x: Int) => x }
b <- actor !!! Req(a) collect { case Res(x: Int) => x }
c <- actor !!! Req(7) collect { case Res(x: String) => x }
Res(a: Int) <- actor !!! Req("Hello")
Res(b: Int) <- actor !!! Req(a)
Res(c: Int) <- actor !!! Req(7)
} yield b + "-" + c
assert(Some(Right("10-14")) === future1.await.value)
intercept[MatchError] { future2.await.resultOrException }
assert(future1.get === "10-14")
intercept[MatchError] { future2.get }
actor.stop()
}
@Test def shouldMapMatchedExceptionsToResult {
val future1 = Future(5)
val future2 = future1 map (_ / 0)
val future3 = future2 map (_.toString)
val future4 = future1 failure {
case e: ArithmeticException => 0
} map (_.toString)
val future5 = future2 failure {
case e: ArithmeticException => 0
} map (_.toString)
val future6 = future2 failure {
case e: MatchError => 0
} map (_.toString)
val future7 = future3 failure { case e: ArithmeticException => "You got ERROR" }
val actor = actorOf[TestActor].start()
val future8 = actor !!! "Failure"
val future9 = actor !!! "Failure" failure {
case e: RuntimeException => "FAIL!"
}
val future10 = actor !!! "Hello" failure {
case e: RuntimeException => "FAIL!"
}
val future11 = actor !!! "Failure" failure { case _ => "Oops!" }
assert(future1.get === 5)
intercept[ArithmeticException] { future2.get }
intercept[ArithmeticException] { future3.get }
assert(future4.get === "5")
assert(future5.get === "0")
intercept[ArithmeticException] { future6.get }
assert(future7.get === "You got ERROR")
intercept[RuntimeException] { future8.get }
assert(future9.get === "FAIL!")
assert(future10.get === "World")
assert(future11.get === "Oops!")
actor.stop()
}
@ -215,8 +260,9 @@ class FutureSpec extends JUnitSuite {
def receive = { case (add: Int, wait: Int) => Thread.sleep(wait); self reply_? add }
}).start()
}
def futures = actors.zipWithIndex map { case (actor: ActorRef, idx: Int) => actor.!!![Int]((idx, idx * 200 )) }
assert(Futures.fold(0)(futures)(_ + _).awaitBlocking.result.get === 45)
val timeout = 10000
def futures = actors.zipWithIndex map { case (actor: ActorRef, idx: Int) => actor.!!![Int]((idx, idx * 200 ), timeout) }
assert(Futures.fold(0, timeout)(futures)(_ + _).await.result.get === 45)
}
@Test def shouldFoldResultsByComposing {
@ -225,8 +271,8 @@ class FutureSpec extends JUnitSuite {
def receive = { case (add: Int, wait: Int) => Thread.sleep(wait); self reply_? add }
}).start()
}
def futures = actors.zipWithIndex map { case (actor: ActorRef, idx: Int) => actor.!!![Int]((idx, idx * 200 )) }
assert(futures.foldLeft(Future(0))((fr, fa) => for (r <- fr; a <- fa) yield (r + a)).awaitBlocking.result.get === 45)
def futures = actors.zipWithIndex map { case (actor: ActorRef, idx: Int) => actor.!!![Int]((idx, idx * 200 ), 10000) }
assert(futures.foldLeft(Future(0))((fr, fa) => for (r <- fr; a <- fa) yield (r + a)).get === 45)
}
@Test def shouldFoldResultsWithException {
@ -240,12 +286,13 @@ class FutureSpec extends JUnitSuite {
}
}).start()
}
def futures = actors.zipWithIndex map { case (actor: ActorRef, idx: Int) => actor.!!![Int]((idx, idx * 100 )) }
assert(Futures.fold(0)(futures)(_ + _).awaitBlocking.exception.get.getMessage === "shouldFoldResultsWithException: expected")
val timeout = 10000
def futures = actors.zipWithIndex map { case (actor: ActorRef, idx: Int) => actor.!!![Int]((idx, idx * 100 ), timeout) }
assert(Futures.fold(0, timeout)(futures)(_ + _).await.exception.get.getMessage === "shouldFoldResultsWithException: expected")
}
@Test def shouldFoldReturnZeroOnEmptyInput {
assert(Futures.fold(0)(List[Future[Int]]())(_ + _).awaitBlocking.result.get === 0)
assert(Futures.fold(0)(List[Future[Int]]())(_ + _).get === 0)
}
@Test def shouldReduceResults {
@ -254,8 +301,9 @@ class FutureSpec extends JUnitSuite {
def receive = { case (add: Int, wait: Int) => Thread.sleep(wait); self reply_? add }
}).start()
}
def futures = actors.zipWithIndex map { case (actor: ActorRef, idx: Int) => actor.!!![Int]((idx, idx * 200 )) }
assert(Futures.reduce(futures)(_ + _).awaitBlocking.result.get === 45)
val timeout = 10000
def futures = actors.zipWithIndex map { case (actor: ActorRef, idx: Int) => actor.!!![Int]((idx, idx * 200 ), timeout) }
assert(Futures.reduce(futures, timeout)(_ + _).get === 45)
}
@Test def shouldReduceResultsWithException {
@ -269,34 +317,15 @@ class FutureSpec extends JUnitSuite {
}
}).start()
}
def futures = actors.zipWithIndex map { case (actor: ActorRef, idx: Int) => actor.!!![Int]((idx, idx * 100 )) }
assert(Futures.reduce(futures)(_ + _).awaitBlocking.exception.get.getMessage === "shouldFoldResultsWithException: expected")
val timeout = 10000
def futures = actors.zipWithIndex map { case (actor: ActorRef, idx: Int) => actor.!!![Int]((idx, idx * 100 ), timeout) }
assert(Futures.reduce(futures, timeout)(_ + _).await.exception.get.getMessage === "shouldFoldResultsWithException: expected")
}
@Test(expected = classOf[UnsupportedOperationException]) def shouldReduceThrowIAEOnEmptyInput {
Futures.reduce(List[Future[Int]]())(_ + _).await.resultOrException
}
@Test def resultWithinShouldNotThrowExceptions {
val latch = new StandardLatch
val actors = (1 to 10).toList map { _ =>
actorOf(new Actor {
def receive = { case (add: Int, wait: Boolean, latch: StandardLatch) => if (wait) latch.await; self reply_? add }
}).start()
}
def futures = actors.zipWithIndex map { case (actor: ActorRef, idx: Int) => actor.!!![Int]((idx, idx >= 5, latch)) }
val result = for(f <- futures) yield f.valueWithin(2, TimeUnit.SECONDS)
latch.open
val done = result collect { case Some(Right(x)) => x }
val undone = result collect { case None => None }
val errors = result collect { case Some(Left(t)) => t }
assert(done.size === 5)
assert(undone.size === 5)
assert(errors.size === 0)
}
@Test def receiveShouldExecuteOnComplete {
val latch = new StandardLatch
val actor = actorOf[TestActor].start()
@ -344,41 +373,289 @@ class FutureSpec extends JUnitSuite {
assert(f3.resultOrException === Some("SUCCESS"))
// make sure all futures are completed in dispatcher
assert(Dispatchers.defaultGlobalDispatcher.futureQueueSize === 0)
assert(Dispatchers.defaultGlobalDispatcher.pendingFutures === 0)
}
@Test def shouldBlockUntilResult {
val latch = new StandardLatch
val f = Future({ latch.await; 5})
val f2 = Future({ f() + 5 })
val f2 = Future({ f.get + 5 })
assert(f2.resultOrException === None)
latch.open
assert(f2() === 10)
assert(f2.get === 10)
val f3 = Future({ Thread.sleep(100); 5}, 10)
intercept[FutureTimeoutException] {
f3()
f3.get
}
}
@Test def lesslessIsMore {
import akka.actor.Actor.spawn
val dataflowVar, dataflowVar2 = new DefaultCompletableFuture[Int](Long.MaxValue)
val begin, end = new StandardLatch
spawn {
begin.await
dataflowVar2 << dataflowVar
end.open
@Test def futureComposingWithContinuations {
import Future.flow
val actor = actorOf[TestActor].start
val x = Future("Hello")
val y = x flatMap (actor !!! _)
val r = flow(x() + " " + y[String]() + "!")
assert(r.get === "Hello World!")
actor.stop
}
@Test def futureComposingWithContinuationsFailureDivideZero {
import Future.flow
val x = Future("Hello")
val y = x map (_.length)
val r = flow(x() + " " + y.map(_ / 0).map(_.toString)(), 100)
intercept[java.lang.ArithmeticException](r.get)
}
@Test def futureComposingWithContinuationsFailureCastInt {
import Future.flow
val actor = actorOf[TestActor].start
val x = Future(3)
val y = actor !!! "Hello"
val r = flow(x() + y[Int](), 100)
intercept[ClassCastException](r.get)
}
@Test def futureComposingWithContinuationsFailureCastNothing {
import Future.flow
val actor = actorOf[TestActor].start
val x = Future("Hello")
val y = actor !!! "Hello"
val r = flow(x() + y())
intercept[ClassCastException](r.get)
}
@Test def futureCompletingWithContinuations {
import Future.flow
val x, y, z = new DefaultCompletableFuture[Int](Actor.TIMEOUT)
val ly, lz = new StandardLatch
val result = flow {
y completeWith x
ly.open // not within continuation
z << x
lz.open // within continuation, will wait for 'z' to complete
z() + y()
}
spawn {
dataflowVar << 5
assert(ly.tryAwaitUninterruptible(100, TimeUnit.MILLISECONDS))
assert(!lz.tryAwaitUninterruptible(100, TimeUnit.MILLISECONDS))
x << 5
assert(y.get === 5)
assert(z.get === 5)
assert(lz.isOpen)
assert(result.get === 10)
val a, b, c = new DefaultCompletableFuture[Int](Actor.TIMEOUT)
val result2 = flow {
val n = (a << c).result.get + 10
b << (c() - 2)
a() + n * b()
}
begin.open
end.await
assert(dataflowVar2() === 5)
assert(dataflowVar.get === 5)
c completeWith Future(5)
assert(a.get === 5)
assert(b.get === 3)
assert(result2.get === 50)
Thread.sleep(100)
// make sure all futures are completed in dispatcher
assert(Dispatchers.defaultGlobalDispatcher.pendingFutures === 0)
}
@Test def shouldNotAddOrRunCallbacksAfterFailureToBeCompletedBeforeExpiry {
val latch = new StandardLatch
val f = new DefaultCompletableFuture[Int](0)
Thread.sleep(25)
f.onComplete( _ => latch.open ) //Shouldn't throw any exception here
assert(f.isExpired) //Should be expired
f.complete(Right(1)) //Shouldn't complete the Future since it is expired
assert(f.value.isEmpty) //Shouldn't be completed
assert(!latch.isOpen) //Shouldn't run the listener
}
@Test def futureDataFlowShouldEmulateBlocking1 {
import Future.flow
val one, two = new DefaultCompletableFuture[Int](1000 * 60)
val simpleResult = flow {
one() + two()
}
assert(List(one, two, simpleResult).forall(_.isCompleted == false))
one << 1
assert(one.isCompleted)
assert(List(two, simpleResult).forall(_.isCompleted == false))
two << 9
assert(List(one, two).forall(_.isCompleted == true))
assert(simpleResult.get === 10)
}
@Test def futureDataFlowShouldEmulateBlocking2 {
import Future.flow
val x1, x2, y1, y2 = new DefaultCompletableFuture[Int](1000 * 60)
val lx, ly, lz = new StandardLatch
val result = flow {
lx.open()
x1 << y1
ly.open()
x2 << y2
lz.open()
x1() + x2()
}
assert(lx.isOpen)
assert(!ly.isOpen)
assert(!lz.isOpen)
assert(List(x1,x2,y1,y2).forall(_.isCompleted == false))
y1 << 1 // When this is set, it should cascade down the line
assert(ly.tryAwaitUninterruptible(2000, TimeUnit.MILLISECONDS))
assert(x1.get === 1)
assert(!lz.isOpen)
y2 << 9 // When this is set, it should cascade down the line
assert(lz.tryAwaitUninterruptible(2000, TimeUnit.MILLISECONDS))
assert(x2.get === 9)
assert(List(x1,x2,y1,y2).forall(_.isCompleted == true))
assert(result.get === 10)
}
@Test def dataFlowAPIshouldbeSlick {
import Future.flow
val i1, i2, s1, s2 = new StandardLatch
val callService1 = Future { i1.open; s1.awaitUninterruptible; 1 }
val callService2 = Future { i2.open; s2.awaitUninterruptible; 9 }
val result = flow { callService1() + callService2() }
assert(!s1.isOpen)
assert(!s2.isOpen)
assert(!result.isCompleted)
assert(i1.tryAwaitUninterruptible(2000, TimeUnit.MILLISECONDS))
assert(i2.tryAwaitUninterruptible(2000, TimeUnit.MILLISECONDS))
s1.open
s2.open
assert(result.get === 10)
}
@Test def futureCompletingWithContinuationsFailure {
import Future.flow
val x, y, z = new DefaultCompletableFuture[Int](Actor.TIMEOUT)
val ly, lz = new StandardLatch
val result = flow {
y << x
ly.open
val oops = 1 / 0
z << x
lz.open
z() + y() + oops
}
assert(!ly.tryAwaitUninterruptible(100, TimeUnit.MILLISECONDS))
assert(!lz.tryAwaitUninterruptible(100, TimeUnit.MILLISECONDS))
x << 5
assert(y.get === 5)
intercept[java.lang.ArithmeticException](result.get)
assert(z.value === None)
assert(!lz.isOpen)
}
@Test def futureContinuationsShouldNotBlock {
import Future.flow
val latch = new StandardLatch
val future = Future {
latch.await
"Hello"
}
val result = flow {
Some(future()).filter(_ == "Hello")
}
assert(!result.isCompleted)
latch.open
assert(result.get === Some("Hello"))
}
@Test def futureFlowShouldBeTypeSafe {
import Future.flow
def checkType[A: Manifest, B](in: Future[A], refmanifest: Manifest[B]): Boolean = manifest[A] == refmanifest
val rString = flow {
val x = Future(5)
x().toString
}
val rInt = flow {
val x = rString.apply
val y = Future(5)
x.length + y()
}
assert(checkType(rString, manifest[String]))
assert(checkType(rInt, manifest[Int]))
assert(!checkType(rInt, manifest[String]))
assert(!checkType(rInt, manifest[Nothing]))
assert(!checkType(rInt, manifest[Any]))
rString.await
rInt.await
}
@Test def ticket812FutureDispatchCleanup {
val dispatcher = implicitly[MessageDispatcher]
assert(dispatcher.pendingFutures === 0)
val future = Future({Thread.sleep(100);"Done"}, 10)
intercept[FutureTimeoutException] { future.await }
assert(dispatcher.pendingFutures === 1)
Thread.sleep(100)
assert(dispatcher.pendingFutures === 0)
}
}

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@ -23,8 +23,8 @@ abstract class MailboxSpec extends
def factory: MailboxType => MessageQueue
name should {
"create a !blockDequeue && unbounded mailbox" in {
val config = UnboundedMailbox(false)
"create an unbounded mailbox" in {
val config = UnboundedMailbox()
val q = factory(config)
ensureInitialMailboxState(config, q)
@ -37,8 +37,8 @@ abstract class MailboxSpec extends
f.await.resultOrException must be === Some(null)
}
"create a !blockDequeue and bounded mailbox with 10 capacity and with push timeout" in {
val config = BoundedMailbox(false, 10, Duration(10,TimeUnit.MILLISECONDS))
"create a bounded mailbox with 10 capacity and with push timeout" in {
val config = BoundedMailbox(10, Duration(10,TimeUnit.MILLISECONDS))
val q = factory(config)
ensureInitialMailboxState(config, q)
@ -59,30 +59,16 @@ abstract class MailboxSpec extends
}
"dequeue what was enqueued properly for unbounded mailboxes" in {
testEnqueueDequeue(UnboundedMailbox(false))
testEnqueueDequeue(UnboundedMailbox())
}
"dequeue what was enqueued properly for bounded mailboxes" in {
testEnqueueDequeue(BoundedMailbox(false, 10000, Duration(-1, TimeUnit.MILLISECONDS)))
testEnqueueDequeue(BoundedMailbox(10000, Duration(-1, TimeUnit.MILLISECONDS)))
}
"dequeue what was enqueued properly for bounded mailboxes with pushTimeout" in {
testEnqueueDequeue(BoundedMailbox(false, 10000, Duration(100, TimeUnit.MILLISECONDS)))
testEnqueueDequeue(BoundedMailbox(10000, Duration(100, TimeUnit.MILLISECONDS)))
}
/** FIXME Adapt test so it works with the last dequeue
"dequeue what was enqueued properly for unbounded mailboxes with blockDeque" in {
testEnqueueDequeue(UnboundedMailbox(true))
}
"dequeue what was enqueued properly for bounded mailboxes with blockDeque" in {
testEnqueueDequeue(BoundedMailbox(true, 1000, Duration(-1, TimeUnit.MILLISECONDS)))
}
"dequeue what was enqueued properly for bounded mailboxes with blockDeque and pushTimeout" in {
testEnqueueDequeue(BoundedMailbox(true, 1000, Duration(100, TimeUnit.MILLISECONDS)))
}*/
}
//CANDIDATE FOR TESTKIT
@ -111,8 +97,8 @@ abstract class MailboxSpec extends
q match {
case aQueue: BlockingQueue[_] =>
config match {
case BoundedMailbox(_,capacity,_) => aQueue.remainingCapacity must be === capacity
case UnboundedMailbox(_) => aQueue.remainingCapacity must be === Int.MaxValue
case BoundedMailbox(capacity,_) => aQueue.remainingCapacity must be === capacity
case UnboundedMailbox() => aQueue.remainingCapacity must be === Int.MaxValue
}
case _ =>
}
@ -165,10 +151,8 @@ abstract class MailboxSpec extends
class DefaultMailboxSpec extends MailboxSpec {
lazy val name = "The default mailbox implementation"
def factory = {
case UnboundedMailbox(blockDequeue) =>
new DefaultUnboundedMessageQueue(blockDequeue)
case BoundedMailbox(blocking, capacity, pushTimeOut) =>
new DefaultBoundedMessageQueue(capacity, pushTimeOut, blocking)
case UnboundedMailbox() => new DefaultUnboundedMessageQueue()
case BoundedMailbox(capacity, pushTimeOut) => new DefaultBoundedMessageQueue(capacity, pushTimeOut)
}
}
@ -176,9 +160,7 @@ class PriorityMailboxSpec extends MailboxSpec {
val comparator = PriorityGenerator(_.##)
lazy val name = "The priority mailbox implementation"
def factory = {
case UnboundedMailbox(blockDequeue) =>
new UnboundedPriorityMessageQueue(blockDequeue, comparator)
case BoundedMailbox(blocking, capacity, pushTimeOut) =>
new BoundedPriorityMessageQueue(capacity, pushTimeOut, blocking, comparator)
case UnboundedMailbox() => new UnboundedPriorityMessageQueue(comparator)
case BoundedMailbox(capacity, pushTimeOut) => new BoundedPriorityMessageQueue(capacity, pushTimeOut, comparator)
}
}

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@ -10,11 +10,11 @@ class PriorityDispatcherSpec extends WordSpec with MustMatchers {
"A PriorityExecutorBasedEventDrivenDispatcher" must {
"Order it's messages according to the specified comparator using an unbounded mailbox" in {
testOrdering(UnboundedMailbox(false))
testOrdering(UnboundedMailbox())
}
"Order it's messages according to the specified comparator using a bounded mailbox" in {
testOrdering(BoundedMailbox(false,1000))
testOrdering(BoundedMailbox(1000))
}
}

View file

@ -16,7 +16,7 @@ import java.net.{InetAddress, UnknownHostException}
*
* @author <a href="http://jonasboner.com">Jonas Bon&#233;r</a>
*/
class AkkaException(message: String = "") extends RuntimeException(message) with Serializable {
class AkkaException(message: String = "", cause: Throwable = null) extends RuntimeException(message, cause) with Serializable {
val uuid = "%s_%s".format(AkkaException.hostname, newUuid)
override lazy val toString = {

View file

@ -67,12 +67,12 @@ case class MaximumNumberOfRestartsWithinTimeRangeReached(
@BeanProperty val lastExceptionCausingRestart: Throwable) extends LifeCycleMessage
// Exceptions for Actors
class ActorStartException private[akka](message: String) extends AkkaException(message)
class IllegalActorStateException private[akka](message: String) extends AkkaException(message)
class ActorKilledException private[akka](message: String) extends AkkaException(message)
class ActorInitializationException private[akka](message: String) extends AkkaException(message)
class ActorTimeoutException private[akka](message: String) extends AkkaException(message)
class InvalidMessageException private[akka](message: String) extends AkkaException(message)
class ActorStartException private[akka](message: String, cause: Throwable = null) extends AkkaException(message, cause)
class IllegalActorStateException private[akka](message: String, cause: Throwable = null) extends AkkaException(message, cause)
class ActorKilledException private[akka](message: String, cause: Throwable = null) extends AkkaException(message, cause)
class ActorInitializationException private[akka](message: String, cause: Throwable = null) extends AkkaException(message, cause)
class ActorTimeoutException private[akka](message: String, cause: Throwable = null) extends AkkaException(message, cause)
class InvalidMessageException private[akka](message: String, cause: Throwable = null) extends AkkaException(message, cause)
/**
* This message is thrown by default when an Actors behavior doesn't match a message
@ -125,7 +125,9 @@ object Actor extends ListenerManagement {
*/
type Receive = PartialFunction[Any, Unit]
private[actor] val actorRefInCreation = new scala.util.DynamicVariable[Option[ActorRef]](None)
private[actor] val actorRefInCreation = new ThreadLocal[Option[ActorRef]]{
override def initialValue = None
}
/**
* Creates an ActorRef out of the Actor with type T.
@ -159,12 +161,15 @@ object Actor extends ListenerManagement {
*/
def actorOf(clazz: Class[_ <: Actor]): ActorRef = new LocalActorRef(() => {
import ReflectiveAccess.{ createInstance, noParams, noArgs }
createInstance[Actor](clazz.asInstanceOf[Class[_]], noParams, noArgs).getOrElse(
throw new ActorInitializationException(
createInstance[Actor](clazz.asInstanceOf[Class[_]], noParams, noArgs) match {
case r: Right[Exception, Actor] => r.b
case l: Left[Exception, Actor] => throw new ActorInitializationException(
"Could not instantiate Actor of " + clazz +
"\nMake sure Actor is NOT defined inside a class/trait," +
"\nif so put it outside the class/trait, f.e. in a companion object," +
"\nOR try to change: 'actorOf[MyActor]' to 'actorOf(new MyActor)'."))
"\nOR try to change: 'actorOf[MyActor]' to 'actorOf(new MyActor)'.", l.a)
}
}, None)
/**
@ -290,7 +295,7 @@ trait Actor {
* the 'forward' function.
*/
@transient implicit val someSelf: Some[ActorRef] = {
val optRef = Actor.actorRefInCreation.value
val optRef = Actor.actorRefInCreation.get
if (optRef.isEmpty) throw new ActorInitializationException(
"ActorRef for instance of actor [" + getClass.getName + "] is not in scope." +
"\n\tYou can not create an instance of an actor explicitly using 'new MyActor'." +
@ -298,7 +303,7 @@ trait Actor {
"\n\tEither use:" +
"\n\t\t'val actor = Actor.actorOf[MyActor]', or" +
"\n\t\t'val actor = Actor.actorOf(new MyActor(..))'")
Actor.actorRefInCreation.value = None
Actor.actorRefInCreation.set(None)
optRef.asInstanceOf[Some[ActorRef]].get.id = getClass.getName //FIXME: Is this needed?
optRef.asInstanceOf[Some[ActorRef]]
}

View file

@ -1015,12 +1015,12 @@ class LocalActorRef private[akka] (
private[this] def newActor: Actor = {
try {
Actor.actorRefInCreation.value = Some(this)
Actor.actorRefInCreation.set(Some(this))
val a = actorFactory()
if (a eq null) throw new ActorInitializationException("Actor instance passed to ActorRef can not be 'null'")
a
} finally {
Actor.actorRefInCreation.value = None
Actor.actorRefInCreation.set(None)
}
}

View file

@ -21,7 +21,6 @@ trait BootableActorLoaderService extends Bootable {
protected def createApplicationClassLoader : Option[ClassLoader] = Some({
if (HOME.isDefined) {
val CONFIG = HOME.get + "/config"
val DEPLOY = HOME.get + "/deploy"
val DEPLOY_DIR = new File(DEPLOY)
if (!DEPLOY_DIR.exists) {

View file

@ -105,13 +105,17 @@ object Scheduler {
}
}
def shutdown: Unit = synchronized {
service.shutdown
def shutdown() {
synchronized {
service.shutdown()
}
}
def restart: Unit = synchronized {
shutdown
service = Executors.newSingleThreadScheduledExecutor(SchedulerThreadFactory)
def restart() {
synchronized {
shutdown()
service = Executors.newSingleThreadScheduledExecutor(SchedulerThreadFactory)
}
}
}

View file

@ -13,7 +13,7 @@ import java.util.concurrent.{CopyOnWriteArrayList, ConcurrentHashMap}
import java.net.InetSocketAddress
import akka.config.Supervision._
class SupervisorException private[akka](message: String) extends AkkaException(message)
class SupervisorException private[akka](message: String, cause: Throwable = null) extends AkkaException(message, cause)
/**
* Factory object for creating supervisors declarative. It creates instances of the 'Supervisor' class.

View file

@ -88,14 +88,14 @@ abstract class UntypedActor extends Actor {
* <p/>
* Is called when an Actor is started by invoking 'actor.start()'.
*/
override def preStart {}
override def preStart() {}
/**
* User overridable callback.
* <p/>
* Is called when 'actor.stop()' is invoked.
*/
override def postStop {}
override def postStop() {}
/**
* User overridable callback.

View file

@ -6,8 +6,8 @@ package akka.config
import akka.AkkaException
class ConfigurationException(message: String) extends AkkaException(message)
class ModuleNotAvailableException(message: String) extends AkkaException(message)
class ConfigurationException(message: String, cause: Throwable = null) extends AkkaException(message, cause)
class ModuleNotAvailableException(message: String, cause: Throwable = null) extends AkkaException(message, cause)
/**
* Loads up the configuration (from the akka.conf file).

View file

@ -23,7 +23,7 @@ object DataFlow {
object Start
object Exit
class DataFlowVariableException(msg: String) extends AkkaException(msg)
class DataFlowVariableException(message: String, cause: Throwable = null) extends AkkaException(message, cause)
/**
* Executes the supplied thunk in another thread.
@ -160,6 +160,6 @@ object DataFlow {
}
}
def shutdown = in ! Exit
def shutdown() { in ! Exit }
}
}

View file

@ -187,14 +187,14 @@ object Dispatchers {
case "GlobalExecutorBasedEventDriven" => GlobalExecutorBasedEventDrivenDispatcherConfigurator
case fqn =>
ReflectiveAccess.getClassFor[MessageDispatcherConfigurator](fqn) match {
case Some(clazz) =>
val instance = ReflectiveAccess.createInstance[MessageDispatcherConfigurator](clazz, Array[Class[_]](), Array[AnyRef]())
if (instance.isEmpty)
throw new IllegalArgumentException("Cannot instantiate MessageDispatcherConfigurator type [%s], make sure it has a default no-args constructor" format fqn)
else
instance.get
case None =>
throw new IllegalArgumentException("Unknown MessageDispatcherConfigurator type [%s]" format fqn)
case r: Right[_, Class[MessageDispatcherConfigurator]] =>
ReflectiveAccess.createInstance[MessageDispatcherConfigurator](r.b, Array[Class[_]](), Array[AnyRef]()) match {
case r: Right[Exception, MessageDispatcherConfigurator] => r.b
case l: Left[Exception, MessageDispatcherConfigurator] =>
throw new IllegalArgumentException("Cannot instantiate MessageDispatcherConfigurator type [%s], make sure it has a default no-args constructor" format fqn, l.a)
}
case l: Left[Exception, _] =>
throw new IllegalArgumentException("Unknown MessageDispatcherConfigurator type [%s]" format fqn, l.a)
}
} map {
_ configure cfg

View file

@ -99,7 +99,7 @@ class ExecutorBasedEventDrivenDispatcher(
registerForExecution(mbox)
}
private[akka] def executeFuture(invocation: FutureInvocation): Unit = if (active.isOn) {
private[akka] def executeFuture(invocation: FutureInvocation[_]): Unit = if (active.isOn) {
try executorService.get() execute invocation
catch {
case e: RejectedExecutionException =>
@ -117,20 +117,14 @@ class ExecutorBasedEventDrivenDispatcher(
def createMailbox(actorRef: ActorRef): AnyRef = mailboxType match {
case b: UnboundedMailbox =>
if (b.blocking) {
new DefaultUnboundedMessageQueue(true) with ExecutableMailbox {
final def dispatcher = ExecutorBasedEventDrivenDispatcher.this
}
} else { //If we have an unbounded, non-blocking mailbox, we can go lockless
new ConcurrentLinkedQueue[MessageInvocation] with MessageQueue with ExecutableMailbox {
final def dispatcher = ExecutorBasedEventDrivenDispatcher.this
final def enqueue(m: MessageInvocation) = this.add(m)
final def dequeue(): MessageInvocation = this.poll()
}
new ConcurrentLinkedQueue[MessageInvocation] with MessageQueue with ExecutableMailbox {
@inline final def dispatcher = ExecutorBasedEventDrivenDispatcher.this
@inline final def enqueue(m: MessageInvocation) = this.add(m)
@inline final def dequeue(): MessageInvocation = this.poll()
}
case b: BoundedMailbox =>
new DefaultBoundedMessageQueue(b.capacity, b.pushTimeOut, b.blocking) with ExecutableMailbox {
final def dispatcher = ExecutorBasedEventDrivenDispatcher.this
new DefaultBoundedMessageQueue(b.capacity, b.pushTimeOut) with ExecutableMailbox {
@inline final def dispatcher = ExecutorBasedEventDrivenDispatcher.this
}
}
@ -294,13 +288,13 @@ trait PriorityMailbox { self: ExecutorBasedEventDrivenDispatcher =>
override def createMailbox(actorRef: ActorRef): AnyRef = self.mailboxType match {
case b: UnboundedMailbox =>
new UnboundedPriorityMessageQueue(b.blocking, comparator) with ExecutableMailbox {
final def dispatcher = self
new UnboundedPriorityMessageQueue(comparator) with ExecutableMailbox {
@inline final def dispatcher = self
}
case b: BoundedMailbox =>
new BoundedPriorityMessageQueue(b.capacity, b.pushTimeOut, b.blocking, comparator) with ExecutableMailbox {
final def dispatcher = self
new BoundedPriorityMessageQueue(b.capacity, b.pushTimeOut, comparator) with ExecutableMailbox {
@inline final def dispatcher = self
}
}
}

View file

@ -10,6 +10,7 @@ import akka.util.{ReflectiveAccess, Switch}
import java.util.Queue
import java.util.concurrent.atomic.{AtomicReference, AtomicInteger}
import java.util.concurrent.{ TimeUnit, ExecutorService, RejectedExecutionException, ConcurrentLinkedQueue, LinkedBlockingQueue}
import util.DynamicVariable
/**
* An executor based event driven dispatcher which will try to redistribute work from busy actors to idle actors. It is assumed
@ -55,6 +56,7 @@ class ExecutorBasedEventDrivenWorkStealingDispatcher(
@volatile private var actorType: Option[Class[_]] = None
@volatile private var members = Vector[ActorRef]()
private val donationInProgress = new DynamicVariable(false)
private[akka] override def register(actorRef: ActorRef) = {
//Verify actor type conformity
@ -78,18 +80,22 @@ class ExecutorBasedEventDrivenWorkStealingDispatcher(
override private[akka] def dispatch(invocation: MessageInvocation) = {
val mbox = getMailbox(invocation.receiver)
/*if (!mbox.isEmpty && attemptDonationOf(invocation, mbox)) {
if (donationInProgress.value == false && (!mbox.isEmpty || mbox.dispatcherLock.locked) && attemptDonationOf(invocation, mbox)) {
//We were busy and we got to donate the message to some other lucky guy, we're done here
} else {*/
} else {
mbox enqueue invocation
registerForExecution(mbox)
//}
}
}
override private[akka] def reRegisterForExecution(mbox: MessageQueue with ExecutableMailbox): Unit = {
while(donateFrom(mbox)) {} //When we reregister, first donate messages to another actor
try {
donationInProgress.value = true
while(donateFrom(mbox)) {} //When we reregister, first donate messages to another actor
} finally { donationInProgress.value = false }
if (!mbox.isEmpty) //If we still have messages left to process, reschedule for execution
super.reRegisterForExecution(mbox)
super.reRegisterForExecution(mbox)
}
/**
@ -110,13 +116,14 @@ class ExecutorBasedEventDrivenWorkStealingDispatcher(
/**
* Returns true if the donation succeeded or false otherwise
*/
/*protected def attemptDonationOf(message: MessageInvocation, donorMbox: MessageQueue with ExecutableMailbox): Boolean = {
protected def attemptDonationOf(message: MessageInvocation, donorMbox: MessageQueue with ExecutableMailbox): Boolean = try {
donationInProgress.value = true
val actors = members // copy to prevent concurrent modifications having any impact
doFindDonorRecipient(donorMbox, actors, System.identityHashCode(message) % actors.size) match {
case null => false
case recipient => donate(message, recipient)
}
}*/
} finally { donationInProgress.value = false }
/**
* Rewrites the message and adds that message to the recipients mailbox

View file

@ -7,18 +7,21 @@ package akka.dispatch
import akka.AkkaException
import akka.event.EventHandler
import akka.actor.{Actor, Channel}
import akka.routing.Dispatcher
import akka.util.Duration
import akka.japi.{ Procedure, Function => JFunc }
import scala.util.continuations._
import java.util.concurrent.locks.ReentrantLock
import java.util.concurrent. {ConcurrentLinkedQueue, TimeUnit, Callable}
import java.util.concurrent.TimeUnit.{NANOSECONDS => NANOS, MILLISECONDS => MILLIS}
import java.util.concurrent.atomic. {AtomicBoolean, AtomicInteger}
import java.util.concurrent.atomic. {AtomicBoolean}
import java.lang.{Iterable => JIterable}
import java.util.{LinkedList => JLinkedList}
import scala.collection.mutable.Stack
import annotation.tailrec
class FutureTimeoutException(message: String) extends AkkaException(message)
class FutureTimeoutException(message: String, cause: Throwable = null) extends AkkaException(message, cause)
object Futures {
@ -199,7 +202,7 @@ object Futures {
// =====================================
// Deprecations
// =====================================
/**
* (Blocking!)
*/
@ -232,11 +235,8 @@ object Future {
* This method constructs and returns a Future that will eventually hold the result of the execution of the supplied body
* The execution is performed by the specified Dispatcher.
*/
def apply[T](body: => T, timeout: Long = Actor.TIMEOUT)(implicit dispatcher: MessageDispatcher): Future[T] = {
val f = new DefaultCompletableFuture[T](timeout)
dispatcher.dispatchFuture(FutureInvocation(f.asInstanceOf[CompletableFuture[Any]], () => body))
f
}
def apply[T](body: => T, timeout: Long = Actor.TIMEOUT)(implicit dispatcher: MessageDispatcher): Future[T] =
dispatcher.dispatchFuture(() => body, timeout)
/**
* Construct a completable channel
@ -274,22 +274,60 @@ object Future {
val fb = fn(a.asInstanceOf[A])
for (r <- fr; b <-fb) yield (r += b)
}.map(_.result)
/**
* Captures a block that will be transformed into 'Continuation Passing Style' using Scala's Delimited
* Continuations plugin.
*
* Within the block, the result of a Future may be accessed by calling Future.apply. At that point
* execution is suspended with the rest of the block being stored in a continuation until the result
* of the Future is available. If an Exception is thrown while processing, it will be contained
* within the resulting Future.
*
* This allows working with Futures in an imperative style without blocking for each result.
*
* Completing a Future using 'CompletableFuture << Future' will also suspend execution until the
* value of the other Future is available.
*
* The Delimited Continuations compiler plugin must be enabled in order to use this method.
*/
def flow[A](body: => A @cps[Future[Any]], timeout: Long = Actor.TIMEOUT): Future[A] = {
val future = new DefaultCompletableFuture[A](timeout)
(reset(future.asInstanceOf[CompletableFuture[Any]].completeWithResult(body)): Future[Any]) onComplete { f =>
val opte = f.exception
if (opte.isDefined) future completeWithException (opte.get)
}
future
}
private[akka] val callbacksPendingExecution = new ThreadLocal[Option[Stack[() => Unit]]]() {
override def initialValue = None
}
}
sealed trait Future[+T] {
/**
* Returns the result of this future after waiting for it to complete,
* this method will throw any throwable that this Future was completed with
* and will throw a java.util.concurrent.TimeoutException if there is no result
* within the Futures timeout
* For use only within a Future.flow block or another compatible Delimited Continuations reset block.
*
* Returns the result of this Future without blocking, by suspending execution and storing it as a
* continuation until the result is available.
*
* If this Future is untyped (a Future[Nothing]), a type parameter must be explicitly provided or
* execution will fail. The normal result of getting a Future from an ActorRef using !!! will return
* an untyped Future.
*/
def apply(): T = this.await.resultOrException.get
def apply[A >: T](): A @cps[Future[Any]] = shift(this flatMap (_: A => Future[Any]))
/**
* Java API for apply()
* Blocks awaiting completion of this Future, then returns the resulting value,
* or throws the completed exception
*
* Scala & Java API
*
* throws FutureTimeoutException if this Future times out when waiting for completion
*/
def get: T = apply()
def get: T = this.await.resultOrException.get
/**
* Blocks the current thread until the Future has been completed or the
@ -298,11 +336,20 @@ sealed trait Future[+T] {
*/
def await : Future[T]
/**
* Blocks the current thread until the Future has been completed or the
* timeout has expired. The timeout will be the least value of 'atMost' and the timeout
* supplied at the constructuion of this Future.
* In the case of the timeout expiring a FutureTimeoutException will be thrown.
*/
def await(atMost: Duration) : Future[T]
/**
* Blocks the current thread until the Future has been completed. Use
* caution with this method as it ignores the timeout and will block
* indefinitely if the Future is never completed.
*/
@deprecated("Will be removed after 1.1, it's dangerous and can cause deadlocks, agony and insanity.")
def awaitBlocking : Future[T]
/**
@ -340,24 +387,6 @@ sealed trait Future[+T] {
else None
}
/**
* Waits for the completion of this Future, then returns the completed value.
* If the Future's timeout expires while waiting a FutureTimeoutException
* will be thrown.
*
* Equivalent to calling future.await.value.
*/
def awaitValue: Option[Either[Throwable, T]]
/**
* Returns the result of the Future if one is available within the specified
* time, if the time left on the future is less than the specified time, the
* time left on the future will be used instead of the specified time.
* returns None if no result, Some(Right(t)) if a result, or
* Some(Left(error)) if there was an exception
*/
def valueWithin(time: Long, unit: TimeUnit): Option[Either[Throwable, T]]
/**
* Returns the contained exception of this Future if it exists.
*/
@ -409,21 +438,18 @@ sealed trait Future[+T] {
final def collect[A](pf: PartialFunction[Any, A]): Future[A] = {
val fa = new DefaultCompletableFuture[A](timeoutInNanos, NANOS)
onComplete { ft =>
val optv = ft.value
if (optv.isDefined) {
val v = optv.get
fa complete {
if (v.isLeft) v.asInstanceOf[Either[Throwable, A]]
else {
try {
val r = v.right.get
if (pf isDefinedAt r) Right(pf(r))
else Left(new MatchError(r))
} catch {
case e: Exception =>
EventHandler.error(e, this, e.getMessage)
Left(e)
}
val v = ft.value.get
fa complete {
if (v.isLeft) v.asInstanceOf[Either[Throwable, A]]
else {
try {
val r = v.right.get
if (pf isDefinedAt r) Right(pf(r))
else Left(new MatchError(r))
} catch {
case e: Exception =>
EventHandler.error(e, this, e.getMessage)
Left(e)
}
}
}
@ -431,6 +457,36 @@ sealed trait Future[+T] {
fa
}
/**
* Creates a new Future that will handle any matching Throwable that this
* Future might contain. If there is no match, or if this Future contains
* a valid result then the new Future will contain the same.
* Example:
* <pre>
* Future(6 / 0) failure { case e: ArithmeticException => 0 } // result: 0
* Future(6 / 0) failure { case e: NotFoundException => 0 } // result: exception
* Future(6 / 2) failure { case e: ArithmeticException => 0 } // result: 3
* </pre>
*/
final def failure[A >: T](pf: PartialFunction[Throwable, A]): Future[A] = {
val fa = new DefaultCompletableFuture[A](timeoutInNanos, NANOS)
onComplete { ft =>
val opte = ft.exception
fa complete {
if (opte.isDefined) {
val e = opte.get
try {
if (pf isDefinedAt e) Right(pf(e))
else Left(e)
} catch {
case x: Exception => Left(x)
}
} else ft.value.get
}
}
fa
}
/**
* Creates a new Future by applying a function to the successful result of
* this Future. If this Future is completed with an exception then the new
@ -456,7 +512,7 @@ sealed trait Future[+T] {
fa complete (try {
Right(f(v.right.get))
} catch {
case e: Exception =>
case e: Exception =>
EventHandler.error(e, this, e.getMessage)
Left(e)
})
@ -492,7 +548,7 @@ sealed trait Future[+T] {
try {
fa.completeWith(f(v.right.get))
} catch {
case e: Exception =>
case e: Exception =>
EventHandler.error(e, this, e.getMessage)
fa completeWithException e
}
@ -508,7 +564,7 @@ sealed trait Future[+T] {
f(optr.get)
}
final def filter(p: T => Boolean): Future[T] = {
final def filter(p: Any => Boolean): Future[Any] = {
val f = new DefaultCompletableFuture[T](timeoutInNanos, NANOS)
onComplete { ft =>
val optv = ft.value
@ -522,7 +578,7 @@ sealed trait Future[+T] {
if (p(r)) Right(r)
else Left(new MatchError(r))
} catch {
case e: Exception =>
case e: Exception =>
EventHandler.error(e, this, e.getMessage)
Left(e)
})
@ -553,7 +609,7 @@ sealed trait Future[+T] {
final def foreach[A >: T](proc: Procedure[A]): Unit = foreach(proc(_))
final def filter[A >: T](p: JFunc[A,Boolean]): Future[T] = filter(p(_))
final def filter(p: JFunc[Any,Boolean]): Future[Any] = filter(p(_))
}
@ -594,10 +650,20 @@ trait CompletableFuture[T] extends Future[T] {
*/
final def << (value: T): Future[T] = complete(Right(value))
/**
* Alias for completeWith(other).
*/
final def << (other : Future[T]): Future[T] = completeWith(other)
final def << (other: Future[T]): Future[T] @cps[Future[Any]] = shift { cont: (Future[T] => Future[Any]) =>
val fr = new DefaultCompletableFuture[Any](Actor.TIMEOUT)
this completeWith other onComplete { f =>
try {
fr completeWith cont(f)
} catch {
case e: Exception =>
EventHandler.error(e, this, e.getMessage)
fr completeWithException e
}
}
fr
}
}
/**
@ -616,45 +682,34 @@ class DefaultCompletableFuture[T](timeout: Long, timeunit: TimeUnit) extends Com
private var _value: Option[Either[Throwable, T]] = None
private var _listeners: List[Future[T] => Unit] = Nil
/**
* Must be called inside _lock.lock<->_lock.unlock
*/
@tailrec
private def awaitUnsafe(wait: Long): Boolean = {
if (_value.isEmpty && wait > 0) {
private def awaitUnsafe(waitTimeNanos: Long): Boolean = {
if (_value.isEmpty && waitTimeNanos > 0) {
val start = currentTimeInNanos
val remaining = try {
_signal.awaitNanos(wait)
val remainingNanos = try {
_signal.awaitNanos(waitTimeNanos)
} catch {
case e: InterruptedException =>
wait - (currentTimeInNanos - start)
waitTimeNanos - (currentTimeInNanos - start)
}
awaitUnsafe(remaining)
awaitUnsafe(remainingNanos)
} else {
_value.isDefined
}
}
def awaitValue: Option[Either[Throwable, T]] = {
def await(atMost: Duration) = {
_lock.lock
try {
awaitUnsafe(timeoutInNanos - (currentTimeInNanos - _startTimeInNanos))
_value
} finally {
_lock.unlock
}
}
def valueWithin(time: Long, unit: TimeUnit): Option[Either[Throwable, T]] = {
_lock.lock
try {
awaitUnsafe(unit.toNanos(time).min(timeoutInNanos - (currentTimeInNanos - _startTimeInNanos)))
_value
} finally {
_lock.unlock
}
if (try { awaitUnsafe(atMost.toNanos min timeLeft()) } finally { _lock.unlock }) this
else throw new FutureTimeoutException("Futures timed out after [" + NANOS.toMillis(timeoutInNanos) + "] milliseconds")
}
def await = {
_lock.lock
if (try { awaitUnsafe(timeoutInNanos - (currentTimeInNanos - _startTimeInNanos)) } finally { _lock.unlock }) this
if (try { awaitUnsafe(timeLeft()) } finally { _lock.unlock }) this
else throw new FutureTimeoutException("Futures timed out after [" + NANOS.toMillis(timeoutInNanos) + "] milliseconds")
}
@ -670,7 +725,7 @@ class DefaultCompletableFuture[T](timeout: Long, timeunit: TimeUnit) extends Com
}
}
def isExpired: Boolean = timeoutInNanos - (currentTimeInNanos - _startTimeInNanos) <= 0
def isExpired: Boolean = timeLeft() <= 0
def value: Option[Either[Throwable, T]] = {
_lock.lock
@ -684,7 +739,7 @@ class DefaultCompletableFuture[T](timeout: Long, timeunit: TimeUnit) extends Com
def complete(value: Either[Throwable, T]): DefaultCompletableFuture[T] = {
_lock.lock
val notifyTheseListeners = try {
if (_value.isEmpty) {
if (_value.isEmpty && !isExpired) { //Only complete if we aren't expired
_value = Some(value)
val existingListeners = _listeners
_listeners = Nil
@ -695,8 +750,29 @@ class DefaultCompletableFuture[T](timeout: Long, timeunit: TimeUnit) extends Com
_lock.unlock
}
if (notifyTheseListeners.nonEmpty)
notifyTheseListeners.reverse foreach notify
if (notifyTheseListeners.nonEmpty) { // Steps to ensure we don't run into a stack-overflow situation
@tailrec def runCallbacks(rest: List[Future[T] => Unit], callbacks: Stack[() => Unit]) {
if (rest.nonEmpty) {
notifyCompleted(rest.head)
while (callbacks.nonEmpty) { callbacks.pop().apply() }
runCallbacks(rest.tail, callbacks)
}
}
val pending = Future.callbacksPendingExecution.get
if (pending.isDefined) { //Instead of nesting the calls to the callbacks (leading to stack overflow)
pending.get.push(() => { // Linearize/aggregate callbacks at top level and then execute
val doNotify = notifyCompleted _ //Hoist closure to avoid garbage
notifyTheseListeners foreach doNotify
})
} else {
try {
val callbacks = Stack[() => Unit]() // Allocate new aggregator for pending callbacks
Future.callbacksPendingExecution.set(Some(callbacks)) // Specify the callback aggregator
runCallbacks(notifyTheseListeners, callbacks) // Execute callbacks, if they trigger new callbacks, they are aggregated
} finally { Future.callbacksPendingExecution.set(None) } // Ensure cleanup
}
}
this
}
@ -705,19 +781,21 @@ class DefaultCompletableFuture[T](timeout: Long, timeunit: TimeUnit) extends Com
_lock.lock
val notifyNow = try {
if (_value.isEmpty) {
_listeners ::= func
false
if(!isExpired) { //Only add the listener if the future isn't expired
_listeners ::= func
false
} else false //Will never run the callback since the future is expired
} else true
} finally {
_lock.unlock
}
if (notifyNow) notify(func)
if (notifyNow) notifyCompleted(func)
this
}
private def notify(func: Future[T] => Unit) {
private def notifyCompleted(func: Future[T] => Unit) {
try {
func(this)
} catch {
@ -725,7 +803,8 @@ class DefaultCompletableFuture[T](timeout: Long, timeunit: TimeUnit) extends Com
}
}
private def currentTimeInNanos: Long = MILLIS.toNanos(System.currentTimeMillis)
@inline private def currentTimeInNanos: Long = MILLIS.toNanos(System.currentTimeMillis)
@inline private def timeLeft(): Long = timeoutInNanos - (currentTimeInNanos - _startTimeInNanos)
}
/**
@ -737,8 +816,7 @@ sealed class AlreadyCompletedFuture[T](suppliedValue: Either[Throwable, T]) exte
def complete(value: Either[Throwable, T]): CompletableFuture[T] = this
def onComplete(func: Future[T] => Unit): Future[T] = { func(this); this }
def awaitValue: Option[Either[Throwable, T]] = value
def valueWithin(time: Long, unit: TimeUnit): Option[Either[Throwable, T]] = value
def await(atMost: Duration): Future[T] = this
def await : Future[T] = this
def awaitBlocking : Future[T] = this
def isExpired: Boolean = true

View file

@ -11,7 +11,7 @@ import java.util.{Queue, List, Comparator, PriorityQueue}
import java.util.concurrent._
import akka.util._
class MessageQueueAppendFailedException(message: String) extends AkkaException(message)
class MessageQueueAppendFailedException(message: String, cause: Throwable = null) extends AkkaException(message, cause)
/**
* @author <a href="http://jonasboner.com">Jonas Bon&#233;r</a>
@ -30,9 +30,8 @@ trait MessageQueue {
*/
sealed trait MailboxType
case class UnboundedMailbox(val blocking: Boolean = false) extends MailboxType
case class UnboundedMailbox() extends MailboxType
case class BoundedMailbox(
val blocking: Boolean = false,
val capacity: Int = { if (Dispatchers.MAILBOX_CAPACITY < 0) Int.MaxValue else Dispatchers.MAILBOX_CAPACITY },
val pushTimeOut: Duration = Dispatchers.MAILBOX_PUSH_TIME_OUT) extends MailboxType {
if (capacity < 0) throw new IllegalArgumentException("The capacity for BoundedMailbox can not be negative")
@ -40,46 +39,35 @@ case class BoundedMailbox(
}
trait UnboundedMessageQueueSemantics extends MessageQueue { self: BlockingQueue[MessageInvocation] =>
def blockDequeue: Boolean
final def enqueue(handle: MessageInvocation) {
this add handle
}
final def dequeue(): MessageInvocation = {
if (blockDequeue) this.take()
else this.poll()
}
@inline final def enqueue(handle: MessageInvocation): Unit = this add handle
@inline final def dequeue(): MessageInvocation = this.poll()
}
trait BoundedMessageQueueSemantics extends MessageQueue { self: BlockingQueue[MessageInvocation] =>
def blockDequeue: Boolean
def pushTimeOut: Duration
final def enqueue(handle: MessageInvocation) {
if (pushTimeOut.length > 0 && pushTimeOut.toMillis > 0) {
if (!this.offer(handle, pushTimeOut.length, pushTimeOut.unit))
throw new MessageQueueAppendFailedException("Couldn't enqueue message " + handle + " to " + toString)
if (pushTimeOut.length > 0) {
this.offer(handle, pushTimeOut.length, pushTimeOut.unit) || {
throw new MessageQueueAppendFailedException("Couldn't enqueue message " + handle + " to " + toString) }
} else this put handle
}
final def dequeue(): MessageInvocation =
if (blockDequeue) this.take()
else this.poll()
@inline final def dequeue(): MessageInvocation = this.poll()
}
class DefaultUnboundedMessageQueue(val blockDequeue: Boolean) extends
class DefaultUnboundedMessageQueue extends
LinkedBlockingQueue[MessageInvocation] with
UnboundedMessageQueueSemantics
class DefaultBoundedMessageQueue(capacity: Int, val pushTimeOut: Duration, val blockDequeue: Boolean) extends
class DefaultBoundedMessageQueue(capacity: Int, val pushTimeOut: Duration) extends
LinkedBlockingQueue[MessageInvocation](capacity) with
BoundedMessageQueueSemantics
class UnboundedPriorityMessageQueue(val blockDequeue: Boolean, cmp: Comparator[MessageInvocation]) extends
class UnboundedPriorityMessageQueue(cmp: Comparator[MessageInvocation]) extends
PriorityBlockingQueue[MessageInvocation](11, cmp) with
UnboundedMessageQueueSemantics
class BoundedPriorityMessageQueue(capacity: Int, val pushTimeOut: Duration, val blockDequeue: Boolean, cmp: Comparator[MessageInvocation]) extends
BoundedBlockingQueue[MessageInvocation](capacity, new PriorityQueue[MessageInvocation](11, cmp)) with
BoundedMessageQueueSemantics
class BoundedPriorityMessageQueue(capacity: Int, val pushTimeOut: Duration, cmp: Comparator[MessageInvocation]) extends
BoundedBlockingQueue[MessageInvocation](capacity, new PriorityQueue[MessageInvocation](11, cmp)) with
BoundedMessageQueueSemantics

View file

@ -5,6 +5,7 @@
package akka.dispatch
import java.util.concurrent._
import java.util.concurrent.atomic.AtomicLong
import akka.event.EventHandler
import akka.config.Configuration
import akka.config.Config.TIME_UNIT
@ -29,16 +30,18 @@ final case class MessageInvocation(val receiver: ActorRef,
}
}
final case class FutureInvocation(future: CompletableFuture[Any], function: () => Any) extends Runnable {
val uuid = akka.actor.newUuid
def run = future complete (try {
Right(function.apply)
} catch {
case e =>
EventHandler.error(e, this, e.getMessage)
Left(e)
})
final case class FutureInvocation[T](future: CompletableFuture[T], function: () => T, cleanup: () => Unit) extends Runnable {
def run = {
future complete (try {
Right(function())
} catch {
case e =>
EventHandler.error(e, this, e.getMessage)
Left(e)
} finally {
cleanup()
})
}
}
object MessageDispatcher {
@ -56,7 +59,7 @@ trait MessageDispatcher {
import MessageDispatcher._
protected val uuids = new ConcurrentSkipListSet[Uuid]
protected val futures = new ConcurrentSkipListSet[Uuid]
protected val futures = new AtomicLong(0L)
protected val guard = new ReentrantGuard
protected val active = new Switch(false)
@ -83,15 +86,27 @@ trait MessageDispatcher {
private[akka] final def dispatchMessage(invocation: MessageInvocation): Unit = dispatch(invocation)
private[akka] final def dispatchFuture(invocation: FutureInvocation): Unit = {
guard withGuard {
futures add invocation.uuid
if (active.isOff) { active.switchOn { start } }
private[akka] final def dispatchFuture[T](block: () => T, timeout: Long): Future[T] = {
futures.getAndIncrement()
try {
val future = new DefaultCompletableFuture[T](timeout)
if (active.isOff)
guard withGuard { active.switchOn { start } }
executeFuture(FutureInvocation[T](future, block, futureCleanup))
future
} catch {
case e =>
futures.decrementAndGet
throw e
}
invocation.future.onComplete { f =>
}
private val futureCleanup: () => Unit =
() => if (futures.decrementAndGet() == 0) {
guard withGuard {
futures remove invocation.uuid
if (futures.isEmpty && uuids.isEmpty) {
if (futures.get == 0 && uuids.isEmpty) {
shutdownSchedule match {
case UNSCHEDULED =>
shutdownSchedule = SCHEDULED
@ -103,8 +118,6 @@ trait MessageDispatcher {
}
}
}
executeFuture(invocation)
}
private[akka] def register(actorRef: ActorRef) {
if (actorRef.mailbox eq null)
@ -121,7 +134,7 @@ trait MessageDispatcher {
private[akka] def unregister(actorRef: ActorRef) = {
if (uuids remove actorRef.uuid) {
actorRef.mailbox = null
if (uuids.isEmpty && futures.isEmpty){
if (uuids.isEmpty && futures.get == 0){
shutdownSchedule match {
case UNSCHEDULED =>
shutdownSchedule = SCHEDULED
@ -155,7 +168,7 @@ trait MessageDispatcher {
shutdownSchedule = SCHEDULED
Scheduler.scheduleOnce(this, timeoutMs, TimeUnit.MILLISECONDS)
case SCHEDULED =>
if (uuids.isEmpty() && futures.isEmpty) {
if (uuids.isEmpty && futures.get == 0) {
active switchOff {
shutdown // shut down in the dispatcher's references is zero
}
@ -187,17 +200,17 @@ trait MessageDispatcher {
*/
private[akka] def dispatch(invocation: MessageInvocation): Unit
private[akka] def executeFuture(invocation: FutureInvocation): Unit
private[akka] def executeFuture(invocation: FutureInvocation[_]): Unit
/**
* Called one time every time an actor is attached to this dispatcher and this dispatcher was previously shutdown
*/
private[akka] def start: Unit
private[akka] def start(): Unit
/**
* Called one time every time an actor is detached from this dispatcher and this dispatcher has no actors left attached
*/
private[akka] def shutdown: Unit
private[akka] def shutdown(): Unit
/**
* Returns the size of the mailbox for the specified actor
@ -205,9 +218,9 @@ trait MessageDispatcher {
def mailboxSize(actorRef: ActorRef): Int
/**
* Returns the size of the Future queue
* Returns the amount of futures queued for execution
*/
def futureQueueSize: Int = futures.size
def pendingFutures: Long = futures.get
}
/**
@ -221,9 +234,8 @@ abstract class MessageDispatcherConfigurator {
def mailboxType(config: Configuration): MailboxType = {
val capacity = config.getInt("mailbox-capacity", Dispatchers.MAILBOX_CAPACITY)
// FIXME how do we read in isBlocking for mailbox? Now set to 'false'.
if (capacity < 1) UnboundedMailbox()
else BoundedMailbox(false, capacity, Duration(config.getInt("mailbox-push-timeout-time", Dispatchers.MAILBOX_PUSH_TIME_OUT.toMillis.toInt), TIME_UNIT))
else BoundedMailbox(capacity, Duration(config.getInt("mailbox-push-timeout-time", Dispatchers.MAILBOX_PUSH_TIME_OUT.toMillis.toInt), TIME_UNIT))
}
def configureThreadPool(config: Configuration, createDispatcher: => (ThreadPoolConfig) => MessageDispatcher): ThreadPoolConfigDispatcherBuilder = {

View file

@ -25,13 +25,13 @@ class ThreadBasedDispatcher(_actor: ActorRef, _mailboxType: MailboxType)
private[akka] val owner = new AtomicReference[ActorRef](_actor)
def this(actor: ActorRef) =
this(actor, UnboundedMailbox(true)) // For Java API
this(actor, UnboundedMailbox()) // For Java API
def this(actor: ActorRef, capacity: Int) =
this(actor, BoundedMailbox(true, capacity)) //For Java API
this(actor, BoundedMailbox(capacity)) //For Java API
def this(actor: ActorRef, capacity: Int, pushTimeOut: Duration) = //For Java API
this(actor, BoundedMailbox(true, capacity, pushTimeOut))
this(actor, BoundedMailbox(capacity, pushTimeOut))
override def register(actorRef: ActorRef) = {
val actor = owner.get()

View file

@ -221,9 +221,9 @@ trait ExecutorServiceDelegate extends ExecutorService {
def execute(command: Runnable) = executor.execute(command)
def shutdown = executor.shutdown
def shutdown() { executor.shutdown() }
def shutdownNow = executor.shutdownNow
def shutdownNow() = executor.shutdownNow()
def isShutdown = executor.isShutdown

View file

@ -102,9 +102,9 @@ object EventHandler extends ListenerManagement {
/**
* Shuts down all event handler listeners including the event handle dispatcher.
*/
def shutdown() = {
foreachListener(_.stop)
EventHandlerDispatcher.shutdown
def shutdown() {
foreachListener(_.stop())
EventHandlerDispatcher.shutdown()
}
def notify(event: Any) {
@ -220,14 +220,15 @@ object EventHandler extends ListenerManagement {
}
defaultListeners foreach { listenerName =>
try {
ReflectiveAccess.getClassFor[Actor](listenerName) map { clazz =>
addListener(Actor.actorOf(clazz).start())
ReflectiveAccess.getClassFor[Actor](listenerName) match {
case r: Right[_, Class[Actor]] => addListener(Actor.actorOf(r.b).start())
case l: Left[Exception,_] => throw l.a
}
} catch {
case e: Exception =>
throw new ConfigurationException(
"Event Handler specified in config can't be loaded [" + listenerName +
"] due to [" + e.toString + "]")
"] due to [" + e.toString + "]", e)
}
}
}

View file

@ -116,7 +116,7 @@ case class RemoteServerWriteFailed(
class RemoteClientException private[akka] (
message: String,
@BeanProperty val client: RemoteClientModule,
val remoteAddress: InetSocketAddress) extends AkkaException(message)
val remoteAddress: InetSocketAddress, cause: Throwable = null) extends AkkaException(message, cause)
/**
* Thrown when the remote server actor dispatching fails for some reason.
@ -143,11 +143,11 @@ abstract class RemoteSupport extends ListenerManagement with RemoteServerModule
handler
}
def shutdown {
def shutdown() {
eventHandler.stop()
removeListener(eventHandler)
this.shutdownClientModule
this.shutdownServerModule
this.shutdownClientModule()
this.shutdownServerModule()
clear
}
@ -189,13 +189,14 @@ abstract class RemoteSupport extends ListenerManagement with RemoteServerModule
def actorOf(clazz: Class[_ <: Actor], host: String, port: Int): ActorRef = {
import ReflectiveAccess.{ createInstance, noParams, noArgs }
clientManagedActorOf(() =>
createInstance[Actor](clazz.asInstanceOf[Class[_]], noParams, noArgs).getOrElse(
throw new ActorInitializationException(
"Could not instantiate Actor" +
"\nMake sure Actor is NOT defined inside a class/trait," +
"\nif so put it outside the class/trait, f.e. in a companion object," +
"\nOR try to change: 'actorOf[MyActor]' to 'actorOf(new MyActor)'.")),
host, port)
createInstance[Actor](clazz.asInstanceOf[Class[_]], noParams, noArgs) match {
case r: Right[_, Actor] => r.b
case l: Left[Exception, _] => throw new ActorInitializationException(
"Could not instantiate Actor" +
"\nMake sure Actor is NOT defined inside a class/trait," +
"\nif so put it outside the class/trait, f.e. in a companion object," +
"\nOR try to change: 'actorOf[MyActor]' to 'actorOf(new MyActor)'.", l.a)
}, host, port)
}
/**
@ -217,13 +218,14 @@ abstract class RemoteSupport extends ListenerManagement with RemoteServerModule
def actorOf[T <: Actor : Manifest](host: String, port: Int): ActorRef = {
import ReflectiveAccess.{ createInstance, noParams, noArgs }
clientManagedActorOf(() =>
createInstance[Actor](manifest[T].erasure.asInstanceOf[Class[_]], noParams, noArgs).getOrElse(
throw new ActorInitializationException(
"Could not instantiate Actor" +
"\nMake sure Actor is NOT defined inside a class/trait," +
"\nif so put it outside the class/trait, f.e. in a companion object," +
"\nOR try to change: 'actorOf[MyActor]' to 'actorOf(new MyActor)'.")),
host, port)
createInstance[Actor](manifest[T].erasure.asInstanceOf[Class[_]], noParams, noArgs) match {
case r: Right[_, Actor] => r.b
case l: Left[Exception, _] => throw new ActorInitializationException(
"Could not instantiate Actor" +
"\nMake sure Actor is NOT defined inside a class/trait," +
"\nif so put it outside the class/trait, f.e. in a companion object," +
"\nOR try to change: 'actorOf[MyActor]' to 'actorOf(new MyActor)'.", l.a)
}, host, port)
}
protected override def manageLifeCycleOfListeners = false
@ -354,7 +356,8 @@ trait RemoteServerModule extends RemoteModule {
def registerByUuid(actorRef: ActorRef): Unit
/**
* Register Remote Actor by a specific 'id' passed as argument.
* Register Remote Actor by a specific 'id' passed as argument. The actor is registered by UUID rather than ID
* when prefixing the handle with the uuid: protocol.
* <p/>
* NOTE: If you use this method to register your remote actor then you must unregister the actor by this ID yourself.
*/

View file

@ -54,7 +54,7 @@ trait DefaultActorPool extends ActorPool { this: Actor =>
private var _lastCapacityChange = 0
private var _lastSelectorCount = 0
override def postStop = _delegates foreach {
override def postStop() = _delegates foreach {
delegate => try {
delegate ! PoisonPill
} catch { case e: Exception => } //Ignore any exceptions here

View file

@ -21,7 +21,7 @@ class AkkaLoader {
* Boot initializes the specified bundles
*/
def boot(withBanner: Boolean, b : Bootable): Unit = hasBooted switchOn {
if (withBanner) printBanner
if (withBanner) printBanner()
println("Starting Akka...")
b.onLoad
Thread.currentThread.setContextClassLoader(getClass.getClassLoader)
@ -32,15 +32,17 @@ class AkkaLoader {
/*
* Shutdown, well, shuts down the bundles used in boot
*/
def shutdown: Unit = hasBooted switchOff {
println("Shutting down Akka...")
_bundles.foreach(_.onUnload)
_bundles = None
Actor.shutdownHook.run
println("Akka succesfully shut down")
def shutdown() {
hasBooted switchOff {
println("Shutting down Akka...")
_bundles.foreach(_.onUnload)
_bundles = None
Actor.shutdownHook.run
println("Akka succesfully shut down")
}
}
private def printBanner = {
private def printBanner() {
println("==================================================")
println(" t")
println(" t t t")

View file

@ -5,6 +5,6 @@
package akka.util
trait Bootable {
def onLoad {}
def onUnload {}
def onLoad() {}
def onUnload() {}
}

View file

@ -42,12 +42,16 @@ object ReflectiveAccess {
lazy val isEnabled = remoteSupportClass.isDefined
def ensureEnabled = if (!isEnabled) {
val e = new ModuleNotAvailableException(
"Can't load the remoting module, make sure that akka-remote.jar is on the classpath")
val e = new ModuleNotAvailableException("Can't load the remoting module, make sure that akka-remote.jar is on the classpath")
EventHandler.debug(this, e.toString)
throw e
}
val remoteSupportClass: Option[Class[_ <: RemoteSupport]] = getClassFor(TRANSPORT)
val remoteSupportClass = getClassFor[RemoteSupport](TRANSPORT) match {
case Right(value) => Some(value)
case Left(exception) =>
EventHandler.debug(this, exception.toString)
None
}
protected[akka] val defaultRemoteSupport: Option[() => RemoteSupport] =
remoteSupportClass map { remoteClass =>
@ -55,9 +59,11 @@ object ReflectiveAccess {
remoteClass,
Array[Class[_]](),
Array[AnyRef]()
) getOrElse {
) match {
case Right(value) => value
case Left(exception) =>
val e = new ModuleNotAvailableException(
"Can't instantiate [%s] - make sure that akka-remote.jar is on the classpath".format(remoteClass.getName))
"Can't instantiate [%s] - make sure that akka-remote.jar is on the classpath".format(remoteClass.getName), exception)
EventHandler.debug(this, e.toString)
throw e
}
@ -85,7 +91,12 @@ object ReflectiveAccess {
"Can't load the typed actor module, make sure that akka-typed-actor.jar is on the classpath")
val typedActorObjectInstance: Option[TypedActorObject] =
getObjectFor("akka.actor.TypedActor$")
getObjectFor[TypedActorObject]("akka.actor.TypedActor$") match {
case Right(value) => Some(value)
case Left(exception)=>
EventHandler.debug(this, exception.toString)
None
}
def resolveFutureIfMessageIsJoinPoint(message: Any, future: Future[_]): Boolean = {
ensureEnabled
@ -111,10 +122,20 @@ object ReflectiveAccess {
lazy val isEnabled = clusterObjectInstance.isDefined
val clusterObjectInstance: Option[AnyRef] =
getObjectFor("akka.cloud.cluster.Cluster$")
getObjectFor[AnyRef]("akka.cloud.cluster.Cluster$") match {
case Right(value) => Some(value)
case Left(exception) =>
EventHandler.debug(this, exception.toString)
None
}
val serializerClass: Option[Class[_]] =
getClassFor("akka.serialization.Serializer")
getClassFor("akka.serialization.Serializer") match {
case Right(value) => Some(value)
case Left(exception) =>
EventHandler.debug(this, exception.toString)
None
}
def ensureEnabled = if (!isEnabled) throw new ModuleNotAvailableException(
"Feature is only available in Akka Cloud")
@ -125,91 +146,88 @@ object ReflectiveAccess {
def createInstance[T](clazz: Class[_],
params: Array[Class[_]],
args: Array[AnyRef]): Option[T] = try {
args: Array[AnyRef]): Either[Exception,T] = try {
assert(clazz ne null)
assert(params ne null)
assert(args ne null)
val ctor = clazz.getDeclaredConstructor(params: _*)
ctor.setAccessible(true)
Some(ctor.newInstance(args: _*).asInstanceOf[T])
Right(ctor.newInstance(args: _*).asInstanceOf[T])
} catch {
case e: Exception =>
EventHandler.debug(this, e.toString)
None
case e: Exception => Left(e)
}
def createInstance[T](fqn: String,
params: Array[Class[_]],
args: Array[AnyRef],
classloader: ClassLoader = loader): Option[T] = try {
classloader: ClassLoader = loader): Either[Exception,T] = try {
assert(params ne null)
assert(args ne null)
getClassFor(fqn) match {
case Some(clazz) =>
val ctor = clazz.getDeclaredConstructor(params: _*)
case Right(value) =>
val ctor = value.getDeclaredConstructor(params: _*)
ctor.setAccessible(true)
Some(ctor.newInstance(args: _*).asInstanceOf[T])
case None => None
Right(ctor.newInstance(args: _*).asInstanceOf[T])
case Left(exception) => Left(exception) //We could just cast this to Either[Exception, T] but it's ugly
}
} catch {
case e: Exception =>
EventHandler.debug(this, e.toString)
None
Left(e)
}
def getObjectFor[T](fqn: String, classloader: ClassLoader = loader): Option[T] = try {//Obtains a reference to $MODULE$
//Obtains a reference to fqn.MODULE$
def getObjectFor[T](fqn: String, classloader: ClassLoader = loader): Either[Exception,T] = try {
getClassFor(fqn) match {
case Some(clazz) =>
val instance = clazz.getDeclaredField("MODULE$")
case Right(value) =>
val instance = value.getDeclaredField("MODULE$")
instance.setAccessible(true)
Option(instance.get(null).asInstanceOf[T])
case None => None
val obj = instance.get(null)
if (obj eq null) Left(new NullPointerException) else Right(obj.asInstanceOf[T])
case Left(exception) => Left(exception) //We could just cast this to Either[Exception, T] but it's ugly
}
} catch {
case e: ExceptionInInitializerError =>
EventHandler.debug(this, e.toString)
throw e
case e: Exception =>
Left(e)
}
def getClassFor[T](fqn: String, classloader: ClassLoader = loader): Option[Class[T]] = {
def getClassFor[T](fqn: String, classloader: ClassLoader = loader): Either[Exception,Class[T]] = try {
assert(fqn ne null)
// First, use the specified CL
val first = try {
Option(classloader.loadClass(fqn).asInstanceOf[Class[T]])
Right(classloader.loadClass(fqn).asInstanceOf[Class[T]])
} catch {
case c: ClassNotFoundException => None
case c: ClassNotFoundException => Left(c)
}
if (first.isDefined) first
if (first.isRight) first
else {
// Second option is to use the ContextClassLoader
val second = try {
Option(Thread.currentThread.getContextClassLoader.loadClass(fqn).asInstanceOf[Class[T]])
Right(Thread.currentThread.getContextClassLoader.loadClass(fqn).asInstanceOf[Class[T]])
} catch {
case c: ClassNotFoundException => None
case c: ClassNotFoundException => Left(c)
}
if (second.isDefined) second
if (second.isRight) second
else {
val third = try {
// Don't try to use "loader" if we got the default "classloader" parameter
if (classloader ne loader) Option(loader.loadClass(fqn).asInstanceOf[Class[T]])
else None
if (classloader ne loader) Right(loader.loadClass(fqn).asInstanceOf[Class[T]]) else Left(null) //Horrid
} catch {
case c: ClassNotFoundException => None
case c: ClassNotFoundException => Left(c)
}
if (third.isDefined) third
if (third.isRight) third
else {
// Last option is Class.forName
try {
Option(Class.forName(fqn).asInstanceOf[Class[T]])
Right(Class.forName(fqn).asInstanceOf[Class[T]]) // Last option is Class.forName
} catch {
case c: ClassNotFoundException => None
case c: ClassNotFoundException => Left(c)
}
}
}
}
} catch {
case e: Exception => Left(e)
}
}

View file

@ -16,7 +16,11 @@ PAPEROPT_letter = -D latex_paper_size=letter
ALLSPHINXOPTS = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) .
# Set python path to include local packages for pygments styles.
PYTHONPATH += $(LOCALPACKAGES)
ifneq (,$(PYTHONPATH))
PYTHONPATH := $(PYTHONPATH):$(LOCALPACKAGES)
else
PYTHONPATH := $(LOCALPACKAGES)
endif
export PYTHONPATH
.PHONY: help clean pygments html singlehtml latex pdf
@ -40,8 +44,11 @@ pygments:
@echo "Custom pygments styles have been installed."
@echo
html: pygments
$(SPHINXBUILD) -b html $(ALLSPHINXOPTS) $(BUILDDIR)/html
$(LOCALPACKAGES):
$(MAKE) pygments
html: $(LOCALPACKAGES)
$(SPHINXBUILD) -a -b html $(ALLSPHINXOPTS) $(BUILDDIR)/html
@echo
@echo "Build finished. The HTML pages are in $(BUILDDIR)/html."

View file

@ -1,23 +1,20 @@
#########
Utilities
#########
.. sidebar:: Contents
.. contents:: :local:
This section of the manual describes miscellaneous utilities which are provided
by Akka and used in multiple places.
.. _Duration:
########
Duration
========
########
Module stability: **SOLID**
Durations are used throughout the Akka library, wherefore this concept is
represented by a special data type, :class:`Duration`. Values of this type may
represent infinite (:obj:`Duration.Inf`, :obj:`Duration.MinusInf`) or finite
durations, where the latter are constructable using a mini-DSL:
durations.
Scala
=====
In Scala durations are constructable using a mini-DSL and support all expected operations:
.. code-block:: scala
@ -27,6 +24,8 @@ durations, where the latter are constructable using a mini-DSL:
val threemillis = 3.millis
val diff = fivesec - threemillis
assert (diff < fivesec)
val fourmillis = threemillis * 4 / 3 // though you cannot write it the other way around
val n = threemillis / (1 millisecond)
.. note::
@ -35,6 +34,9 @@ durations, where the latter are constructable using a mini-DSL:
if the time unit is the last token on a line, otherwise semi-colon inference
might go wrong, depending on what starts the next line.
Java
====
Java provides less syntactic sugar, so you have to spell out the operations as
method calls instead:

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@ -0,0 +1,8 @@
Common utilities
==========================
.. toctree::
:maxdepth: 2
scheduler
duration

View file

@ -0,0 +1,23 @@
Scheduler
=========
Module stability: **SOLID**
``Akka`` has a little scheduler written using actors.
This can be convenient if you want to schedule some periodic task for maintenance or similar.
It allows you to register a message that you want to be sent to a specific actor at a periodic interval.
Here is an example:
-------------------
.. code-block:: scala
import akka.actor.Scheduler
//Sends messageToBeSent to receiverActor after initialDelayBeforeSending and then after each delayBetweenMessages
Scheduler.schedule(receiverActor, messageToBeSent, initialDelayBeforeSending, delayBetweenMessages, timeUnit)
//Sends messageToBeSent to receiverActor after delayUntilSend
Scheduler.scheduleOnce(receiverActor, messageToBeSent, delayUntilSend, timeUnit)

View file

@ -13,7 +13,7 @@ extensions = ['sphinx.ext.todo', 'includecode']
templates_path = ['_templates']
source_suffix = '.rst'
master_doc = 'index'
exclude_patterns = ['_build', 'pending']
exclude_patterns = ['_build', 'pending', 'disabled']
project = u'Akka'
copyright = u'2009-2011, Scalable Solutions AB'

View file

@ -6,25 +6,25 @@ Code Style
The Akka code style follows `this document <http://davetron5000.github.com/scala-style/ScalaStyleGuide.pdf>`_ .
Here is a code style settings file for IntelliJ IDEA.
`<file:akka-intellij-code-style.jar>`_
Here is a code style settings file for ``IntelliJ IDEA``:
`Download <http://scalablesolutions.se/akka/docs/akka-0.10/files/akka-intellij-code-style.jar>`_
Please follow the code style. Look at the code around you and mimic.
Testing
-------
All code that is checked in should have tests. All testing is done with ScalaTest and ScalaCheck.
All code that is checked in **should** have tests. All testing is done with ``ScalaTest`` and ``ScalaCheck``.
* Name tests as *Test.scala if they do not depend on any external stuff. That keeps surefire happy.
* Name tests as *Spec.scala if they have external dependencies.
* Name tests as **Test.scala** if they do not depend on any external stuff. That keeps surefire happy.
* Name tests as **Spec.scala** if they have external dependencies.
There is a testing standard that should be followed: `Ticket001Spec <@https://github.com/jboner/akka/blob/master/akka-actor/src/test/scala/akka/ticket/Ticket001Spec.scala>`_
There is a testing standard that should be followed: `Ticket001Spec <https://github.com/jboner/akka/blob/master/akka-actor-tests/src/test/scala/akka/ticket/Ticket001Spec.scala>`_
Actor TestKit
^^^^^^^^^^^^^
There is a useful test kit for testing actors: `akka.util.TestKit <@https://github.com/jboner/akka/tree/master/akka-actor/src/main/scala/akka/util/TestKit.scala>`_. It enables assertions concerning replies received and their timing, there is more documentation in the `<TestKit>`_ module.
There is a useful test kit for testing actors: `akka.util.TestKit <https://github.com/jboner/akka/tree/master/akka-testkit/src/main/scala/akka/testkit/TestKit.scala>`_. It enables assertions concerning replies received and their timing, there is more documentation in the `<TestKit>`_ module.
NetworkFailureTest
^^^^^^^^^^^^^^^^^^

View file

@ -7,6 +7,10 @@
Documentation
###############
.. sidebar:: Contents
.. contents:: :local:
The Akka documentation uses `reStructuredText`_ as its markup language and is
built using `Sphinx`_.
@ -67,3 +71,83 @@ For example::
Here is a reference to "akka section": :ref:`akka-section` which will have the
name "Akka Section".
Build the documentation
=======================
First install `Sphinx`_. See below.
Building
--------
::
cd akka-docs
make html
open _build/html/index.html
make pdf
open _build/latex/Akka.pdf
Installing Sphinx on OS X
-------------------------
Install `Homebrew <https://github.com/mxcl/homebrew>`_
Install Python and pip:
::
brew install python
/usr/local/share/python/easy_install pip
Add the Homebrew Python path to your $PATH:
::
/usr/local/Cellar/python/2.7.1/bin
More information in case of trouble:
https://github.com/mxcl/homebrew/wiki/Homebrew-and-Python
Install sphinx:
::
pip install sphinx
Add sphinx_build to your $PATH:
::
/usr/local/share/python
Install BasicTeX package from:
http://www.tug.org/mactex/morepackages.html
Add texlive bin to $PATH:
::
/usr/local/texlive/2010basic/bin/universal-darwin
Add missing tex packages:
::
sudo tlmgr update --self
sudo tlmgr install titlesec
sudo tlmgr install framed
sudo tlmgr install threeparttable
sudo tlmgr install wrapfig
sudo tlmgr install helvetic
sudo tlmgr install courier
Link the akka pygments style:
::
cd /usr/local/Cellar/python/2.7.1/lib/python2.7/site-packages/pygments/styles
ln -s /path/to/akka/akka-docs/themes/akka/pygments/akka.py akka.py

View file

@ -5,3 +5,6 @@ Information for Developers
:maxdepth: 2
documentation
developer-guidelines
sponsors
team

View file

@ -1,11 +1,5 @@
****<span style="font-size: 150%;">Sponsors </span>****
=======================================================
Scalable Solutions
==================
Scalable Solutions AB is the commercial entity behind Akka, providing support, consulting and training around Akka.
`<http://scalablesolutions.se>`_
Sponsors
============
YourKit
=======

25
akka-docs/dev/team.rst Normal file
View file

@ -0,0 +1,25 @@
Team
=====
=================== ========================== =================================
Name Role Email
=================== ========================== =================================
Jonas Bonér Founder, Despot, Committer jonas AT jonasboner DOT com
Viktor Klang Bad cop, Committer viktor DOT klang AT gmail DOT com
Debasish Ghosh Committer dghosh AT acm DOT org
Ross McDonald Alumni rossajmcd AT gmail DOT com
Eckhart Hertzler Alumni
Mikael Högqvist Alumni
Tim Perrett Alumni
Jeanfrancois Arcand Alumni jfarcand AT apache DOT org
Martin Krasser Committer krasserm AT googlemail DOT com
Jan Van Besien Alumni
Michael Kober Alumni
Peter Vlugter Committer
Peter Veentjer Committer
Irmo Manie Committer
Heiko Seeberger Committer
Hiram Chirino Committer
Scott Clasen Committer
Roland Kuhn Committer
=================== ========================== =================================

View file

@ -91,11 +91,11 @@ object Pi extends App {
}
//#master-receive
override def preStart {
override def preStart() {
start = now
}
override def postStop {
override def postStop() {
// tell the world that the calculation is complete
println(
"\n\tPi estimate: \t\t%s\n\tCalculation time: \t%s millis"

View file

@ -19,14 +19,17 @@ We will be using an algorithm that is called "embarrassingly parallel" which jus
Here is the formula for the algorithm we will use:
.. image:: pi-formula.png
.. image:: ../images/pi-formula.png
In this particular algorithm the master splits the series into chunks which are sent out to each worker actor to be processed. When each worker has processed its chunk it sends a result back to the master which aggregates the total result.
Tutorial source code
--------------------
If you want don't want to type in the code and/or set up an SBT project then you can check out the full tutorial from the Akka GitHub repository. It is in the ``akka-tutorials/akka-tutorial-first`` module. You can also browse it online `here <https://github.com/jboner/akka/tree/master/akka-tutorials/akka-tutorial-first>`_, with the actual source code `here <https://github.com/jboner/akka/blob/master/akka-tutorials/akka-tutorial-first/src/main/scala/Pi.scala>`_.
If you want don't want to type in the code and/or set up an SBT project then you can check out the full tutorial from the Akka GitHub repository. It is in the ``akka-tutorials/akka-tutorial-first`` module. You can also browse it online `here`__, with the actual source code `here`__.
__ https://github.com/jboner/akka/tree/master/akka-tutorials/akka-tutorial-first
__ https://github.com/jboner/akka/blob/master/akka-tutorials/akka-tutorial-first/src/main/scala/Pi.scala
Prerequisites
-------------

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@ -0,0 +1,173 @@
.. highlightlang:: none
.. _building-akka:
###############
Building Akka
###############
This page describes how to build and run Akka from the latest source code.
.. contents:: :local:
Get the source code
===================
Akka uses `Git`_ and is hosted at `Github`_.
.. _Git: http://git-scm.com
.. _Github: http://github.com
You first need Git installed on your machine. You can then clone the source
repositories:
- Akka repository from http://github.com/jboner/akka
- Akka Modules repository from http://github.com/jboner/akka-modules
For example::
git clone git://github.com/jboner/akka.git
git clone git://github.com/jboner/akka-modules.git
If you have already cloned the repositories previously then you can update the
code with ``git pull``::
git pull origin master
SBT - Simple Build Tool
=======================
Akka is using the excellent `SBT`_ build system. So the first thing you have to
do is to download and install SBT. You can read more about how to do that in the
`SBT setup`_ documentation.
.. _SBT: http://code.google.com/p/simple-build-tool
.. _SBT setup: http://code.google.com/p/simple-build-tool/wiki/Setup
The SBT commands that you'll need to build Akka are all included below. If you
want to find out more about SBT and using it for your own projects do read the
`SBT documentation`_.
.. _SBT documentation: http://code.google.com/p/simple-build-tool/wiki/RunningSbt
The Akka SBT build file is ``project/build/AkkaProject.scala`` with some
properties defined in ``project/build.properties``.
Building Akka
=============
First make sure that you are in the akka code directory::
cd akka
Fetching dependencies
---------------------
SBT does not fetch dependencies automatically. You need to manually do this with
the ``update`` command::
sbt update
Once finished, all the dependencies for Akka will be in the ``lib_managed``
directory under each module: akka-actor, akka-stm, and so on.
*Note: you only need to run update the first time you are building the code,
or when the dependencies have changed.*
Building
--------
To compile all the Akka core modules use the ``compile`` command::
sbt compile
You can run all tests with the ``test`` command::
sbt test
If compiling and testing are successful then you have everything working for the
latest Akka development version.
Publish to local Ivy repository
-------------------------------
If you want to deploy the artifacts to your local Ivy repository (for example,
to use from an SBT project) use the ``publish-local`` command::
sbt publish-local
Publish to local Maven repository
---------------------------------
If you want to deploy the artifacts to your local Maven repository use::
sbt publish-local publish
SBT interactive mode
--------------------
Note that in the examples above we are calling ``sbt compile`` and ``sbt test``
and so on. SBT also has an interactive mode. If you just run ``sbt`` you enter
the interactive SBT prompt and can enter the commands directly. This saves
starting up a new JVM instance for each command and can be much faster and more
convenient.
For example, building Akka as above is more commonly done like this::
% sbt
[info] Building project akka 1.1-SNAPSHOT against Scala 2.9.0.RC1
[info] using AkkaParentProject with sbt 0.7.6.RC0 and Scala 2.7.7
> update
[info]
[info] == akka-actor / update ==
...
[success] Successful.
[info]
[info] Total time ...
> compile
...
> test
...
SBT batch mode
--------------
It's also possible to combine commands in a single call. For example, updating,
testing, and publishing Akka to the local Ivy repository can be done with::
sbt update test publish-local
Building Akka Modules
=====================
See the Akka Modules documentation.
Dependencies
============
If you are managing dependencies by hand you can find the dependencies for each
module by looking in the ``lib_managed`` directories. For example, this will
list all compile dependencies (providing you have the source code and have run
``sbt update``)::
cd akka
ls -1 */lib_managed/compile
You can also look at the Ivy dependency resolution information that is created
on ``sbt update`` and found in ``~/.ivy2/cache``. For example, the
``.ivy2/cache/se.scalablesolutions.akka-akka-remote-compile.xml`` file contains
the resolution information for the akka-remote module compile dependencies. If
you open this file in a web browser you will get an easy to navigate view of
dependencies.

View file

@ -0,0 +1,103 @@
Configuration
=============
.. sidebar:: Contents
.. contents:: :local:
Specifying the configuration file
---------------------------------
If you don't specify a configuration file then Akka uses default values, corresponding to the ``akka-reference.conf``
that you see below. You can specify your own configuration file to override any property in the reference config.
You only have to define the properties that differ from the default configuration.
The location of the config file to use can be specified in various ways:
* Define the ``-Dakka.config=...`` system property parameter with a file path to configuration file.
* Put an ``akka.conf`` file in the root of the classpath.
* Define the ``AKKA_HOME`` environment variable pointing to the root of the Akka
distribution. The config is taken from the ``AKKA_HOME/config/akka.conf``. You
can also point to the AKKA_HOME by specifying the ``-Dakka.home=...`` system
property parameter.
If several of these ways to specify the config file are used at the same time the precedence is the order as given above,
i.e. you can always redefine the location with the ``-Dakka.config=...`` system property.
Defining the configuration file
-------------------------------
Here is the reference configuration file:
.. literalinclude:: ../../config/akka-reference.conf
:language: none
A custom ``akka.conf`` might look like this:
::
# In this file you can override any option defined in the 'akka-reference.conf' file.
# Copy in all or parts of the 'akka-reference.conf' file and modify as you please.
akka {
event-handlers = ["akka.event.slf4j.Slf4jEventHandler"]
# Comma separated list of the enabled modules.
enabled-modules = ["camel", "remote"]
# These boot classes are loaded (and created) automatically when the Akka Microkernel boots up
# Can be used to bootstrap your application(s)
# Should be the FQN (Fully Qualified Name) of the boot class which needs to have a default constructor
boot = ["sample.camel.Boot",
"sample.myservice.Boot"]
actor {
throughput = 10 # Throughput for ExecutorBasedEventDrivenDispatcher, set to 1 for complete fairness
}
remote {
server {
port = 2562 # The port clients should connect to. Default is 2552 (AKKA)
}
}
}
Specifying files for different modes
------------------------------------
You can use different configuration files for different purposes by specifying a mode option, either as
``-Dakka.mode=...`` system property or as ``AKKA_MODE=...`` environment variable. For example using DEBUG log level
when in development mode. Run with ``-Dakka.mode=dev`` and place the following ``akka.dev.conf`` in the root of
the classpath.
akka.dev.conf:
::
akka {
event-handler-level = "DEBUG"
}
The mode option works in the same way when using configuration files in ``AKKA_HOME/config/`` directory.
The mode option is not used when specifying the configuration file with ``-Dakka.config=...`` system property.
Including files
---------------
Sometimes it can be useful to include another configuration file, for example if you have one ``akka.conf`` with all
environment independent settings and then override some settings for specific modes.
akka.dev.conf:
::
include "akka.conf"
akka {
event-handler-level = "DEBUG"
}

View file

@ -12,7 +12,8 @@ You can configure which event handlers should be registered at boot time. That i
.. code-block:: ruby
akka {
event-handlers = ["akka.event.EventHandler$DefaultListener"] # event handlers to register at boot time (EventHandler$DefaultListener logs to STDOUT)
# event handlers to register at boot time (EventHandler$DefaultListener logs to STDOUT)
event-handlers = ["akka.event.EventHandler$DefaultListener"]
event-handler-level = "DEBUG" # Options: ERROR, WARNING, INFO, DEBUG
}
@ -88,9 +89,10 @@ The methods take a call-by-name parameter for the message to avoid object alloca
From Java you need to nest the call in an if statement to achieve the same thing.
`<code format="scala">`_
if (EventHandler.isDebugEnabled()) {
EventHandler.debug(this, String.format("Processing took %s ms", duration));
}
.. code-block:: java
if (EventHandler.isDebugEnabled()) {
EventHandler.debug(this, String.format("Processing took %s ms", duration));
}
`<code>`_

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@ -4,5 +4,10 @@ General
.. toctree::
:maxdepth: 2
jmm
migration-guides
util
building-akka
configuration
event-handler
issue-tracking
licenses

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@ -0,0 +1,56 @@
Issue Tracking
==============
Akka is using ``Assembla`` as issue tracking system.
Browsing
--------
Tickets
^^^^^^^
`You can find the Akka tickets here <http://www.assembla.com/spaces/akka>`_
`You can find the Akka Modules tickets here <https://www.assembla.com/spaces/akka-modules/tickets>`_
Roadmaps
^^^^^^^^
`The roadmap for each Akka milestone is here <https://www.assembla.com/spaces/akka/milestones>`_
`The roadmap for each Akka Modules milestone is here <https://www.assembla.com/spaces/akka-modules/milestones>`_
Creating tickets
----------------
In order to create tickets you need to do the following:
`Register here <https://www.assembla.com/user/signup>`_ then log in
For Akka tickets:
`Link to create new ticket <https://www.assembla.com/spaces/akka/tickets/new>`_
For Akka Modules tickets:
`Link to create new ticket <https://www.assembla.com/spaces/akka-modules/tickets>`_
Thanks a lot for reporting bugs and suggesting features.
Failing test
------------
Please submit a failing test on the following format:
.. code-block:: scala
import org.scalatest.WordSpec
import org.scalatest.matchers.MustMatchers
class Ticket001Spec extends WordSpec with MustMatchers {
"An XXX" should {
"do YYY" in {
1 must be (1)
}
}
}

33
akka-docs/general/jmm.rst Normal file
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@ -0,0 +1,33 @@
Akka and the Java Memory Model
================================
Prior to Java 5, the Java Memory Model (JMM) was broken. It was possible to get all kinds of strange results like unpredictable merged writes made by concurrent executing threads, unexpected reordering of instructions, and even final fields were not guaranteed to be final. With Java 5 and JSR-133, the Java Memory Model is clearly specified. This specification makes it possible to write code that performs, but doesn't cause concurrency problems. The Java Memory Model is specified in 'happens before'-rules, e.g.:
* **monitor lock rule**: a release of a lock happens before every subsequent acquire of the same lock.
* **volatile variable rule**: a write of a volatile variable happens before every subsequent read of the same volatile variable
The 'happens before'-rules clearly specify which visibility guarantees are provided on memory and which re-orderings are allowed. Without these rules it would not be possible to write concurrent and performant code in Java.
Actors and the Java Memory Model
--------------------------------
With the Actors implementation in Akka, there are 2 ways multiple threads can execute actions on shared memory over time:
* if a message is send to an actor (e.g. by another actor). In most cases messages are immutable, but if that message is not a properly constructed immutable object, without happens before rules, the system still could be subject to instruction re-orderings and visibility problems (so a possible source of concurrency errors).
* if an actor makes changes to its internal state in one 'receive' method and access that state while processing another message. With the actors model you don't get any guarantee that the same thread will be executing the same actor for different messages. Without a happens before relation between these actions, there could be another source of concurrency errors.
To solve the 2 problems above, Akka adds the following 2 'happens before'-rules to the JMM:
* **the actor send rule**: where the send of the message to an actor happens before the receive of the **same** actor.
* **the actor subsequent processing rule**: where processing of one message happens before processing of the next message by the **same** actor.
Both rules only apply for the same actor instance and are not valid if different actors are used.
STM and the Java Memory Model
-----------------------------
The Akka STM also provides a happens before rule called:
* **the transaction rule**: a commit on a transaction happens before every subsequent start of a transaction where there is at least 1 shared reference.
How these rules are realized in Akka, is an implementation detail and can change over time (the exact details could even depend on the used configuration) but they will lift on the other JMM rules like the monitor lock rule or the volatile variable rule. Essentially this means that you, the Akka user, do not need to worry about adding synchronization to provide such a happens before relation, because it is the responsibility of Akka. So you have your hands free to deal with your problems and not that of the framework.

View file

@ -38,4 +38,4 @@ Akka Remote
Akka Testkit
------------
The TestKit moved into the akka-testkit subproject and correspondingly into the :code:`akka.testkit` package.
The TestKit moved into the akka-testkit subproject and correspondingly into the ``akka.testkit`` package.

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@ -6,7 +6,9 @@ Contents
intro/index
general/index
common/index
scala/index
java/index
dev/index
Links

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@ -1,340 +0,0 @@
Building Akka
=============
This page describes how to build and run Akka from the latest source code.
.. contents:: :local:
Get the source code
-------------------
Akka uses `Git <http://git-scm.com>`_ and is hosted at `Github
<http://github.com>`_.
You first need Git installed on your machine. You can then clone the source
repositories:
- Akka repository from `<http://github.com/jboner/akka>`_
- Akka Modules repository from `<http://github.com/jboner/akka-modules>`_
For example::
git clone git://github.com/jboner/akka.git
git clone git://github.com/jboner/akka-modules.git
If you have already cloned the repositories previously then you can update the
code with ``git pull``::
git pull origin master
SBT - Simple Build Tool
-----------------------
Akka is using the excellent `SBT <http://code.google.com/p/simple-build-tool>`_
build system. So the first thing you have to do is to download and install
SBT. You can read more about how to do that `here
<http://code.google.com/p/simple-build-tool/wiki/Setup>`_ .
The SBT commands that you'll need to build Akka are all included below. If you
want to find out more about SBT and using it for your own projects do read the
`SBT documentation
<http://code.google.com/p/simple-build-tool/wiki/RunningSbt>`_.
The Akka SBT build file is ``project/build/AkkaProject.scala`` with some
properties defined in ``project/build.properties``.
Building Akka
-------------
First make sure that you are in the akka code directory::
cd akka
Fetching dependencies
^^^^^^^^^^^^^^^^^^^^^
SBT does not fetch dependencies automatically. You need to manually do this with
the ``update`` command::
sbt update
Once finished, all the dependencies for Akka will be in the ``lib_managed``
directory under each module: akka-actor, akka-stm, and so on.
*Note: you only need to run update the first time you are building the code,
or when the dependencies have changed.*
Building
^^^^^^^^
To compile all the Akka core modules use the ``compile`` command::
sbt compile
You can run all tests with the ``test`` command::
sbt test
If compiling and testing are successful then you have everything working for the
latest Akka development version.
Publish to local Ivy repository
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
If you want to deploy the artifacts to your local Ivy repository (for example,
to use from an SBT project) use the ``publish-local`` command::
sbt publish-local
Publish to local Maven repository
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
If you want to deploy the artifacts to your local Maven repository use::
sbt publish-local publish
SBT interactive mode
^^^^^^^^^^^^^^^^^^^^
Note that in the examples above we are calling ``sbt compile`` and ``sbt test``
and so on. SBT also has an interactive mode. If you just run ``sbt`` you enter
the interactive SBT prompt and can enter the commands directly. This saves
starting up a new JVM instance for each command and can be much faster and more
convenient.
For example, building Akka as above is more commonly done like this:
.. code-block:: none
% sbt
[info] Building project akka 1.1-SNAPSHOT against Scala 2.9.0.RC1
[info] using AkkaParentProject with sbt 0.7.6.RC0 and Scala 2.7.7
> update
[info]
[info] == akka-actor / update ==
...
[success] Successful.
[info]
[info] Total time ...
> compile
...
> test
...
SBT batch mode
^^^^^^^^^^^^^^
It's also possible to combine commands in a single call. For example, updating,
testing, and publishing Akka to the local Ivy repository can be done with::
sbt update test publish-local
Building Akka Modules
---------------------
To build Akka Modules first build and publish Akka to your local Ivy repository
as described above. Or using::
cd akka
sbt update publish-local
Then you can build Akka Modules using the same steps as building Akka. First
update to get all dependencies (including the Akka core modules), then compile,
test, or publish-local as needed. For example::
cd akka-modules
sbt update publish-local
Microkernel distribution
^^^^^^^^^^^^^^^^^^^^^^^^
To build the Akka Modules microkernel (the same as the Akka Modules distribution
download) use the ``dist`` command::
sbt dist
The distribution zip can be found in the dist directory and is called
``akka-modules-{version}.zip``.
To run the microkernel, unzip the zip file, change into the unzipped directory,
set the ``AKKA_HOME`` environment variable, and run the main jar file. For
example:
.. code-block:: none
unzip dist/akka-modules-1.1-SNAPSHOT.zip
cd akka-modules-1.1-SNAPSHOT
export AKKA_HOME=`pwd`
java -jar akka-modules-1.1-SNAPSHOT.jar
The microkernel will boot up and install the sample applications that reside in
the distribution's ``deploy`` directory. You can deploy your own applications
into the ``deploy`` directory as well.
Scripts
-------
Linux/Unix init script
^^^^^^^^^^^^^^^^^^^^^^
Here is a Linux/Unix init script that can be very useful:
http://github.com/jboner/akka/blob/master/scripts/akka-init-script.sh
Copy and modify as needed.
Simple startup shell script
^^^^^^^^^^^^^^^^^^^^^^^^^^^
This little script might help a bit. Just make sure you have the Akka
distribution in the '$AKKA_HOME/dist' directory and then invoke this script to
start up the kernel. The distribution is created in the './dist' dir for you if
you invoke 'sbt dist'.
http://github.com/jboner/akka/blob/master/scripts/run_akka.sh
Copy and modify as needed.
Dependencies
------------
If you are managing dependencies by hand you can find out what all the compile
dependencies are for each module by looking in the ``lib_managed/compile``
directories. For example, you can run this to create a listing of dependencies
(providing you have the source code and have run ``sbt update``)::
cd akka
ls -1 */lib_managed/compile
Dependencies used by the Akka core modules
------------------------------------------
akka-actor
^^^^^^^^^^
* No dependencies
akka-stm
^^^^^^^^
* Depends on akka-actor
* multiverse-alpha-0.6.2.jar
akka-typed-actor
^^^^^^^^^^^^^^^^
* Depends on akka-stm
* aopalliance-1.0.jar
* aspectwerkz-2.2.3.jar
* guice-all-2.0.jar
akka-remote
^^^^^^^^^^^
* Depends on akka-typed-actor
* commons-codec-1.4.jar
* commons-io-2.0.1.jar
* dispatch-json_2.8.1-0.7.8.jar
* guice-all-2.0.jar
* h2-lzf-1.0.jar
* jackson-core-asl-1.7.1.jar
* jackson-mapper-asl-1.7.1.jar
* junit-4.8.1.jar
* netty-3.2.3.Final.jar
* objenesis-1.2.jar
* protobuf-java-2.3.0.jar
* sjson_2.8.1-0.9.1.jar
akka-http
^^^^^^^^^
* Depends on akka-remote
* jsr250-api-1.0.jar
* jsr311-api-1.1.jar
Dependencies used by the Akka modules
-------------------------------------
akka-amqp
^^^^^^^^^
* Depends on akka-remote
* commons-cli-1.1.jar
* amqp-client-1.8.1.jar
akka-camel
^^^^^^^^^^
* Depends on akka-actor
* camel-core-2.7.0.jar
* commons-logging-api-1.1.jar
* commons-management-1.0.jar
akka-camel-typed
^^^^^^^^^^^^^^^^
* Depends on akka-typed-actor
* camel-core-2.7.0.jar
* commons-logging-api-1.1.jar
* commons-management-1.0.jar
akka-spring
^^^^^^^^^^^
* Depends on akka-camel
* akka-camel-typed
* commons-logging-1.1.1.jar
* spring-aop-3.0.4.RELEASE.jar
* spring-asm-3.0.4.RELEASE.jar
* spring-beans-3.0.4.RELEASE.jar
* spring-context-3.0.4.RELEASE.jar
* spring-core-3.0.4.RELEASE.jar
* spring-expression-3.0.4.RELEASE.jar
akka-scalaz
^^^^^^^^^^^
* Depends on akka-actor
* hawtdispatch-1.1.jar
* hawtdispatch-scala-1.1.jar
* scalaz-core_2.8.1-6.0-SNAPSHOT.jar
akka-kernel
^^^^^^^^^^^
* Depends on akka-http, akka-amqp, and akka-spring
* activation-1.1.jar
* asm-3.1.jar
* jaxb-api-2.1.jar
* jaxb-impl-2.1.12.jar
* jersey-core-1.3.jar
* jersey-json-1.3.jar
* jersey-scala-1.3.jar
* jersey-server-1.3.jar
* jettison-1.1.jar
* jetty-continuation-7.1.6.v20100715.jar
* jetty-http-7.1.6.v20100715.jar
* jetty-io-7.1.6.v20100715.jar
* jetty-security-7.1.6.v20100715.jar
* jetty-server-7.1.6.v20100715.jar
* jetty-servlet-7.1.6.v20100715.jar
* jetty-util-7.1.6.v20100715.jar
* jetty-xml-7.1.6.v20100715.jar
* servlet-api-2.5.jar
* stax-api-1.0.1.jar

View file

@ -1,31 +0,0 @@
Configuration
=============
Specifying the configuration file
---------------------------------
If you don't specify a configuration file then Akka uses default values. If
you want to override these then you should edit the ``akka.conf`` file in the
``AKKA_HOME/config`` directory. This config inherits from the
``akka-reference.conf`` file that you see below. Use your ``akka.conf`` to override
any property in the reference config.
The config can be specified in various ways:
* Define the ``-Dakka.config=...`` system property option
* Put an ``akka.conf`` file on the classpath
* Define the ``AKKA_HOME`` environment variable pointing to the root of the Akka
distribution. The config is taken from the ``AKKA_HOME/config`` directory. You
can also point to the AKKA_HOME by specifying the ``-Dakka.home=...`` system
property option.
Defining the configuration file
-------------------------------
Here is the reference configuration file:
.. literalinclude:: ../../config/akka-reference.conf
:language: none

View file

@ -19,14 +19,25 @@ We will be using an algorithm that is called "embarrassingly parallel" which jus
Here is the formula for the algorithm we will use:
.. image:: pi-formula.png
.. image:: ../images/pi-formula.png
In this particular algorithm the master splits the series into chunks which are sent out to each worker actor to be processed. When each worker has processed its chunk it sends a result back to the master which aggregates the total result.
Tutorial source code
--------------------
If you want don't want to type in the code and/or set up a Maven project then you can check out the full tutorial from the Akka GitHub repository. It is in the ``akka-tutorials/akka-tutorial-first`` module. You can also browse it online `here <https://github.com/jboner/akka/tree/master/akka-tutorials/akka-tutorial-first>`_, with the actual source code `here <https://github.com/jboner/akka/blob/master/akka-tutorials/akka-tutorial-first/src/main/java/akka/tutorial/first/java/Pi.java>`_.
If you want don't want to type in the code and/or set up a Maven project then you can check out the full tutorial from the Akka GitHub repository. It is in the ``akka-tutorials/akka-tutorial-first`` module. You can also browse it online `here`__, with the actual source code `here`__.
__ https://github.com/jboner/akka/tree/master/akka-tutorials/akka-tutorial-first
__ https://github.com/jboner/akka/blob/master/akka-tutorials/akka-tutorial-first/src/main/java/akka/tutorial/first/java/Pi.java
To check out the code using Git invoke the following::
$ git clone git://github.com/jboner/akka.git
Then you can navigate down to the tutorial::
$ cd akka/akka-tutorials/akka-tutorial-first
Prerequisites
-------------

View file

@ -1,3 +1,5 @@
.. _getting-started-first-scala-eclipse:
Getting Started Tutorial (Scala with Eclipse): First Chapter
============================================================
@ -12,14 +14,17 @@ We will be using an algorithm that is called "embarrassingly parallel" which jus
Here is the formula for the algorithm we will use:
.. image:: pi-formula.png
.. image:: ../images/pi-formula.png
In this particular algorithm the master splits the series into chunks which are sent out to each worker actor to be processed. When each worker has processed its chunk it sends a result back to the master which aggregates the total result.
Tutorial source code
--------------------
If you want don't want to type in the code and/or set up an SBT project then you can check out the full tutorial from the Akka GitHub repository. It is in the ``akka-tutorials/akka-tutorial-first`` module. You can also browse it online `here <https://github.com/jboner/akka/tree/master/akka-tutorials/akka-tutorial-first>`_, with the actual source code `here <https://github.com/jboner/akka/blob/master/akka-tutorials/akka-tutorial-first/src/main/scala/Pi.scala>`_.
If you want don't want to type in the code and/or set up an SBT project then you can check out the full tutorial from the Akka GitHub repository. It is in the ``akka-tutorials/akka-tutorial-first`` module. You can also browse it online `here`__, with the actual source code `here`__.
__ https://github.com/jboner/akka/tree/master/akka-tutorials/akka-tutorial-first
__ https://github.com/jboner/akka/blob/master/akka-tutorials/akka-tutorial-first/src/main/scala/Pi.scala
Prerequisites
-------------
@ -99,19 +104,19 @@ If you want to use Eclipse for coding your Akka tutorial, you need to install th
You can install this plugin using the regular update mechanism. First choose a version of the IDE from `http://download.scala-ide.org <http://download.scala-ide.org>`_. We recommend you choose 2.0.x, which comes with Scala 2.9. Copy the corresponding URL and then choose ``Help/Install New Software`` and paste the URL you just copied. You should see something similar to the following image.
.. image:: install-beta2-updatesite.png
.. image:: ../images/install-beta2-updatesite.png
Make sure you select both the ``JDT Weaving for Scala`` and the ``Scala IDE for Eclipse`` plugins. The other plugin is optional, and contains the source code of the plugin itself.
Once the installation is finished, you need to restart Eclipse. The first time the plugin starts it will open a diagnostics window and offer to fix several settings, such as the delay for content assist (code-completion) or the shown completion proposal types.
.. image:: diagnostics-window.png
.. image:: ../images/diagnostics-window.png
Accept the recommended settings, and follow the instructions if you need to increase the heap size of Eclipse.
Check that the installation succeeded by creating a new Scala project (``File/New>Scala Project``), and typing some code. You should have content-assist, hyperlinking to definitions, instant error reporting, and so on.
.. image:: example-code.png
.. image:: ../images/example-code.png
You are ready to code now!
@ -140,7 +145,7 @@ Creating an Akka project in Eclipse
If you have not already done so, now is the time to create an Eclipse project for our tutorial. Use the ``New Scala Project`` wizard and accept the default settings. Once the project is open, we need to add the akka libraries to the *build path*. Right click on the project and choose ``Properties``, then click on ``Java Build Path``. Go to ``Libraries`` and click on ``Add External Jars..``, then navigate to the location where you installed akka and choose ``akka-actor.jar``. You should see something similar to this:
.. image:: build-path.png
.. image:: ../images/build-path.png
Using SBT in Eclipse
^^^^^^^^^^^^^^^^^^^^
@ -186,7 +191,7 @@ Then run the ``eclipse`` target to generate the Eclipse project::
Next you need to import this project in Eclipse, by choosing ``Eclipse/Import.. Existing Projects into Workspace``. Navigate to the directory where you defined your SBT project and choose import:
.. image:: import-project.png
.. image:: ../images/import-project.png
Now we have the basis for an Akka Eclipse application, so we can..
@ -234,7 +239,7 @@ Now we can create the worker actor. Create a new class called ``Worker`` as bef
The ``Actor`` trait is defined in ``akka.actor`` and you can either import it explicitly, or let Eclipse do it for you when it cannot resolve the ``Actor`` trait. The quick fix option (``Ctrl-F1``) will offer two options:
.. image:: quickfix.png
.. image:: ../images/quickfix.png
Choose the Akka Actor and move on.
@ -307,11 +312,11 @@ Here is the master actor::
def receive = { ... }
override def preStart {
override def preStart() {
start = System.currentTimeMillis
}
override def postStop {
override def postStop() {
// tell the world that the calculation is complete
println(
"\n\tPi estimate: \t\t%s\n\tCalculation time: \t%s millis"
@ -403,7 +408,7 @@ If you have not defined an the ``AKKA_HOME`` environment variable then Akka can'
You can also define a new Run configuration, by going to ``Run/Run Configurations``. Create a new ``Scala application`` and choose the tutorial project and the main class to be ``akkatutorial.Pi``. You can pass additional command line arguments to the JVM on the ``Arguments`` page, for instance to define where ``akka.conf`` is:
.. image:: run-config.png
.. image:: ../images/run-config.png
Once you finished your run configuration, click ``Run``. You should see the same output in the ``Console`` window. You can use the same configuration for debugging the application, by choosing ``Run/Debug History`` or just ``Debug As``.

View file

@ -19,14 +19,25 @@ We will be using an algorithm that is called "embarrassingly parallel" which jus
Here is the formula for the algorithm we will use:
.. image:: pi-formula.png
.. image:: ../images/pi-formula.png
In this particular algorithm the master splits the series into chunks which are sent out to each worker actor to be processed. When each worker has processed its chunk it sends a result back to the master which aggregates the total result.
Tutorial source code
--------------------
If you want don't want to type in the code and/or set up an SBT project then you can check out the full tutorial from the Akka GitHub repository. It is in the ``akka-tutorials/akka-tutorial-first`` module. You can also browse it online `here <https://github.com/jboner/akka/tree/master/akka-tutorials/akka-tutorial-first>`_, with the actual source code `here <https://github.com/jboner/akka/blob/master/akka-tutorials/akka-tutorial-first/src/main/scala/Pi.scala>`_.
If you want don't want to type in the code and/or set up an SBT project then you can check out the full tutorial from the Akka GitHub repository. It is in the ``akka-tutorials/akka-tutorial-first`` module. You can also browse it online `here`__, with the actual source code `here`__.
__ https://github.com/jboner/akka/tree/master/akka-tutorials/akka-tutorial-first
__ https://github.com/jboner/akka/blob/master/akka-tutorials/akka-tutorial-first/src/main/scala/Pi.scala
To check out the code using Git invoke the following::
$ git clone git://github.com/jboner/akka.git
Then you can navigate down to the tutorial::
$ cd akka/akka-tutorials/akka-tutorial-first
Prerequisites
-------------
@ -173,8 +184,11 @@ Not needed in this tutorial, but if you would like to use additional Akka module
So, now we are all set. Just one final thing to do; make SBT download the dependencies it needs. That is done by invoking::
> reload
> update
The first reload command is needed because we have changed the project definition since the sbt session started.
SBT itself needs a whole bunch of dependencies but our project will only need one; ``akka-actor-1.1.jar``. SBT downloads that as well.
Start writing the code
@ -291,11 +305,11 @@ Here is the master actor::
def receive = { ... }
override def preStart {
override def preStart() {
start = System.currentTimeMillis
}
override def postStop {
override def postStop() {
// tell the world that the calculation is complete
println(
"\n\tPi estimate: \t\t%s\n\tCalculation time: \t%s millis"
@ -451,11 +465,11 @@ But before we package it up and run it, let's take a look at the full code now,
if (nrOfResults == nrOfMessages) self.stop()
}
override def preStart {
override def preStart() {
start = System.currentTimeMillis
}
override def postStop {
override def postStop() {
// tell the world that the calculation is complete
println(
"\n\tPi estimate: \t\t%s\n\tCalculation time: \t%s millis"

View file

@ -4,9 +4,8 @@ Introduction
.. toctree::
:maxdepth: 2
what-is-akka
why-akka
getting-started-first-scala
getting-started-first-scala-eclipse
getting-started-first-java
building-akka
configuration

View file

@ -0,0 +1,33 @@
What is Akka?
====
**Akka**
^^^^^^
**Simpler Scalability, Fault-Tolerance, Concurrency & Remoting through Actors**
We believe that writing correct concurrent, fault-tolerant and scalable applications is too hard. Most of the time it's because we are using the wrong tools and the wrong level of abstraction. Akka is here to change that. Using the Actor Model together with ``Software Transactional Memory`` we raise the abstraction level and provide a better platform to build correct concurrent and scalable applications. For fault-tolerance we adopt the ``Let it crash`` / ``Embrace failure`` model which have been used with great success in the telecom industry to build applications that self-heals, systems that never stop. Actors also provides the abstraction for transparent distribution and the basis for truly scalable and fault-tolerant applications. Akka is Open Source and available under the ``Apache 2 License``.
Download from `<http://akka.io/downloads/>`_
**Akka implements a unique hybrid of:**
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
* `Actors <untyped-actors-java>`_, which gives you:
* Simple and high-level abstractions for concurrency and parallelism.
* Asynchronous, non-blocking and highly performant event-driven programming model.
* Very lightweight event-driven processes (create ~6.5 million actors on 4GB RAM).
* `Failure management <fault-tolerance-java>`_ through supervisor hierarchies with `let-it-crash <http://letitcrash.com>`_ semantics. Excellent for writing highly fault-tolerant systems that never stop, systems that self-heal.
* `Software Transactional Memory <stm-java>`_ (STM). (Distributed transactions coming soon).
* `Transactors <transactors-java>`_: combine actors and STM into transactional actors. Allows you to compose atomic message flows with automatic retry and rollback.
* `Remote actors <remote-actors-java>`_: highly performant distributed actors with remote supervision and error management.
* Java and Scala API.
**Akka can be used in two different ways:**
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
* As a library: used by a web app, to be put into WEB-INF/lib or as a regular JAR on your classpath.
* As a microkernel: stand-alone kernel, embedding a servlet container and all the other modules.
See the `Use-case and Deployment Scenarios <deployment-scenarios>`_ for details.

View file

@ -1,6 +1,10 @@
Dispatchers (Java)
==================
.. sidebar:: Contents
.. contents:: :local:
Module stability: **SOLID**
The Dispatcher is an important piece that allows you to configure the right semantics and parameters for optimal performance, throughput and scalability. Different Actors have different needs.
@ -128,7 +132,7 @@ If you don't define a the 'throughput' option in the configuration file then the
Browse the `ScalaDoc <scaladoc>`_ or look at the code for all the options available.
Priority event-based
^^^^^^^^^^^
^^^^^^^^^^^^^^^^^^^^
Sometimes it's useful to be able to specify priority order of messages, that is done by using PriorityExecutorBasedEventDrivenDispatcher and supply
a java.util.Comparator[MessageInvocation] or use a akka.dispatch.PriorityGenerator (recommended):
@ -137,7 +141,7 @@ Creating a PriorityExecutorBasedEventDrivenDispatcher using PriorityGenerator:
.. code-block:: java
package some.package;
package some.pkg;
import akka.actor.*;
import akka.dispatch.*;
@ -249,13 +253,14 @@ For the 'ExecutorBasedEventDrivenDispatcher' and the 'ExecutorBasedWorkStealingD
For the 'ThreadBasedDispatcher', it is non-shareable between actors, and associates a dedicated Thread with the actor.
Making it bounded (by specifying a capacity) is optional, but if you do, you need to provide a pushTimeout (default is 10 seconds). When trying to send a message to the Actor it will throw a MessageQueueAppendFailedException("BlockingMessageTransferQueue transfer timed out") if the message cannot be added to the mailbox within the time specified by the pushTimeout.
`<code format="java">`_
class MyActor extends UntypedActor {
public MyActor() {
int mailboxCapacity = 100;
Duration pushTimeout = new FiniteDuration(10, TimeUnit.SECONDS);
getContext().setDispatcher(Dispatchers.newThreadBasedDispatcher(getContext(), mailboxCapacity, pushTimeout));
.. code-block:: java
class MyActor extends UntypedActor {
public MyActor() {
int mailboxCapacity = 100;
Duration pushTimeout = new FiniteDuration(10, TimeUnit.SECONDS);
getContext().setDispatcher(Dispatchers.newThreadBasedDispatcher(getContext(), mailboxCapacity, pushTimeout));
}
...
}
...
}
`<code>`_

14
akka-docs/java/index.rst Normal file
View file

@ -0,0 +1,14 @@
Java API
=========
.. toctree::
:maxdepth: 2
untyped-actors
typed-actors
actor-registry
stm
transactors
remote-actors
serialization
dispatchers

View file

@ -1,11 +1,15 @@
Remote Actors (Java)
====================
.. sidebar:: Contents
.. contents:: :local:
Module stability: **SOLID**
Akka supports starting UntypedActors and TypedActors on remote nodes using a very efficient and scalable NIO implementation built upon `JBoss Netty <http://jboss.org/netty>`_ and `Google Protocol Buffers <http://code.google.com/p/protobuf/>`_ .
Akka supports starting interacting with UntypedActors and TypedActors on remote nodes using a very efficient and scalable NIO implementation built upon `JBoss Netty <http://jboss.org/netty>`_ and `Google Protocol Buffers <http://code.google.com/p/protobuf/>`_ .
The usage is completely transparent both in regards to sending messages and error handling and propagation as well as supervision, linking and restarts. You can send references to other Actors as part of the message.
The usage is completely transparent with local actors, both in regards to sending messages and error handling and propagation as well as supervision, linking and restarts. You can send references to other Actors as part of the message.
**WARNING**: For security reasons, do not run an Akka node with a Remote Actor port reachable by untrusted connections unless you have supplied a classloader that restricts access to the JVM.
@ -142,12 +146,6 @@ The default behavior is that the remote client will maintain a transaction log o
If you choose a capacity higher than 0, then a bounded queue will be used and if the limit of the queue is reached then a 'RemoteClientMessageBufferException' will be thrown.
You can also get an Array with all the messages that the remote client has failed to send. Since the remote client events passes you an instance of the RemoteClient you have an easy way to act upon failure and do something with these messages (while waiting for them to be retried).
.. code-block:: java
Object[] pending = Actors.remote().pendingMessages();
Running Remote Server in untrusted mode
---------------------------------------
@ -253,21 +251,13 @@ You can also generate the secure cookie by using the 'Crypt' object and its 'gen
The secure cookie is a cryptographically secure randomly generated byte array turned into a SHA-1 hash.
Remote Actors
-------------
Akka has two types of remote actors:
* Client-initiated and managed. Here it is the client that creates the remote actor and "moves it" to the server.
* Server-initiated and managed. Here it is the server that creates the remote actor and the client can ask for a handle to this actor.
They are good for different use-cases. The client-initiated are great when you want to monitor an actor on another node since it allows you to link to it and supervise it using the regular supervision semantics. They also make RPC completely transparent. The server-initiated, on the other hand, are great when you have a service running on the server that you want clients to connect to, and you want full control over the actor on the server side for security reasons etc.
Client-managed Remote UntypedActor
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
----------------------------------
DEPRECATED AS OF 1.1
The client creates the remote actor and "moves it" to the server.
When you define an actors as being remote it is instantiated as on the remote host and your local actor becomes a proxy, it works as a handle to the remote actor. The real execution is always happening on the remote node.
Here is an example:
@ -291,26 +281,31 @@ An UntypedActor can also start remote child Actors through one of the “spawn/l
.. code-block:: java
...
getContext().spawnRemote(MyActor.class, hostname, port);
getContext().spawnRemote(MyActor.class, hostname, port, timeoutInMsForFutures);
getContext().spawnLinkRemote(MyActor.class, hostname, port, timeoutInMsForFutures);
...
Server-managed Remote UntypedActor
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
----------------------------------
Here it is the server that creates the remote actor and the client can ask for a handle to this actor.
Server side setup
*****************
^^^^^^^^^^^^^^^^^
The API for server managed remote actors is really simple. 2 methods only:
.. code-block:: java
import akka.actor.Actors;
import akka.actor.UntypedActor;
class MyActor extends UntypedActor {
public void onReceive(Object message) throws Exception {
...
}
}
Actors.remote().start("localhost", 2552).register("hello-service", Actors.actorOf(HelloWorldActor.class);
Actors.remote().start("localhost", 2552).register("hello-service", Actors.actorOf(HelloWorldActor.class));
Actors created like this are automatically started.
@ -322,88 +317,6 @@ You can also register an actor by its UUID rather than ID or handle. This is don
server.unregister("uuid:" + actor.uuid);
Client side usage
*****************
.. code-block:: java
ActorRef actor = Actors.remote().actorFor("hello-service", "localhost", 2552);
actor.sendOneWay("Hello");
There are many variations on the 'remote()#actorFor' method. Here are some of them:
.. code-block:: java
... = actorFor(className, hostname, port);
... = actorFor(className, timeout, hostname, port);
... = actorFor(uuid, className, hostname, port);
... = actorFor(uuid, className, timeout, hostname, port);
... // etc
All of these also have variations where you can pass in an explicit 'ClassLoader' which can be used when deserializing messages sent from the remote actor.
Client-managed Remote TypedActor
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
DEPRECATED AS OF 1.1
Remote Typed Actors are created through the 'TypedActor.newRemoteInstance' factory method.
.. code-block:: java
MyPOJO remoteActor = (MyPOJO)TypedActor.newRemoteInstance(MyPOJO.class, MyPOJOImpl.class, , "localhost", 2552);
And if you want to specify the timeout:
.. code-block:: java
MyPOJO remoteActor = (MyPOJO)TypedActor.newRemoteInstance(MyPOJO.class, MyPOJOImpl.class, timeout, "localhost", 2552);
You can also define the Typed Actor to be a client-managed-remote service by adding the RemoteAddress configuration element in the declarative supervisor configuration:
.. code-block:: java
new Component(
Foo.class,
FooImpl.class,
new LifeCycle(new Permanent(), 1000),
1000,
new RemoteAddress("localhost", 2552))
Server-managed Remote TypedActor
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
WARNING: Remote TypedActors do not work with overloaded methods on your TypedActor, refrain from using overloading.
Server side setup
*****************
The API for server managed remote typed actors is nearly the same as for untyped actor:
.. code-block:: java
import static akka.actor.Actors.*;
remote().start("localhost", 2552);
RegistrationService typedActor = TypedActor.newInstance(RegistrationService.class, RegistrationServiceImpl.class, 2000);
remote().registerTypedActor("user-service", typedActor);
Client side usage
.. code-block:: java
import static akka.actor.Actors.*;
RegistrationService actor = remote().typedActorFor(RegistrationService.class, "user-service", 5000L, "localhost", 2552);
actor.registerUser(...);
There are variations on the 'remote()#typedActorFor' method. Here are some of them:
.. code-block:: java
... = typedActorFor(interfaceClazz, serviceIdOrClassName, hostname, port);
... = typedActorFor(interfaceClazz, serviceIdOrClassName, timeout, hostname, port);
... = typedActorFor(interfaceClazz, serviceIdOrClassName, timeout, hostname, port, classLoader);
Session bound server side setup
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -414,17 +327,19 @@ Session bound actors are useful if you need to keep state per session, e.g. user
.. code-block:: java
import static akka.actor.Actors.*;
import akka.japi.Creator;
class HelloWorldActor extends Actor {
...
}
remote().start("localhost", 2552);
remote().registerPerSession("hello-service", new Creator[ActorRef]() {
remote().registerPerSession("hello-service", new Creator<ActorRef>() {
public ActorRef create() {
return actorOf(HelloWorldActor.class);
}
})
});
Note that the second argument in registerPerSession is a Creator, it means that the create method will create a new ActorRef each invocation.
It will be called to create an actor every time a session is established.
@ -443,19 +358,22 @@ There are many variations on the 'remote()#actorFor' method. Here are some of th
.. code-block:: java
... = actorFor(className, hostname, port);
... = actorFor(className, timeout, hostname, port);
... = actorFor(uuid, className, hostname, port);
... = actorFor(uuid, className, timeout, hostname, port);
... = remote().actorFor(className, hostname, port);
... = remote().actorFor(className, timeout, hostname, port);
... = remote().actorFor(uuid, className, hostname, port);
... = remote().actorFor(uuid, className, timeout, hostname, port);
... // etc
Automatic remote 'sender' reference management
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
All of these also have variations where you can pass in an explicit 'ClassLoader' which can be used when deserializing messages sent from the remote actor.
Akka is automatically remote-enabling the sender Actor reference for you in order to allow the receiver to respond to the message using 'getContext().getSender().sendOneWay(msg);' or 'getContext().reply(msg);'. By default it is registering the sender reference in the remote server with the 'hostname' and 'port' from the akka.conf configuration file. The default is "localhost" and 2552 and if there is no remote server with this hostname and port then it creates and starts it.
Automatic remote 'sender' reference management
----------------------------------------------
The sender of a remote message will be reachable with a reply through the remote server on the node that the actor is residing, automatically.
Please note that firewalled clients won't work right now. [2011-01-05]
Identifying remote actors
^^^^^^^^^^^^^^^^^^^^^^^^^
-------------------------
The 'id' field in the 'Actor' class is of importance since it is used as identifier for the remote actor. If you want to create a brand new actor every time you instantiate a remote actor then you have to set the 'id' field to a unique 'String' for each instance. If you want to reuse the same remote actor instance for each new remote actor (of the same class) you create then you don't have to do anything since the 'id' field by default is equal to the name of the actor class.
@ -463,18 +381,83 @@ Here is an example of overriding the 'id' field:
.. code-block:: java
import akka.util.UUID;
import akka.actor.UntypedActor;
import com.eaio.uuid.UUID;
class MyActor extends UntypedActor {
public MyActor() {
getContext().setId(UUID.newUuid().toString());
getContext().setId(new UUID().toString());
}
public void onReceive(Object message) throws Exception {
...
// ...
}
}
Client-managed Remote Typed Actors
----------------------------------
DEPRECATED AS OF 1.1
Remote Typed Actors are created through the 'TypedActor.newRemoteInstance' factory method.
.. code-block:: java
MyPOJO remoteActor = (MyPOJO) TypedActor.newRemoteInstance(MyPOJO.class, MyPOJOImpl.class, "localhost", 2552);
And if you want to specify the timeout:
.. code-block:: java
MyPOJO remoteActor = (MyPOJO)TypedActor.newRemoteInstance(MyPOJO.class, MyPOJOImpl.class, timeout, "localhost", 2552);
You can also define the Typed Actor to be a client-managed-remote service by adding the RemoteAddress configuration element in the declarative supervisor configuration:
.. code-block:: java
new Component(
Foo.class,
FooImpl.class,
new LifeCycle(new Permanent(), 1000),
1000,
new RemoteAddress("localhost", 2552))
Server-managed Remote Typed Actors
----------------------------------
WARNING: Remote TypedActors do not work with overloaded methods on your TypedActor, refrain from using overloading.
Server side setup
^^^^^^^^^^^^^^^^^
The API for server managed remote typed actors is nearly the same as for untyped actor:
.. code-block:: java
import static akka.actor.Actors.*;
remote().start("localhost", 2552);
RegistrationService typedActor = TypedActor.newInstance(RegistrationService.class, RegistrationServiceImpl.class, 2000);
remote().registerTypedActor("user-service", typedActor);
Client side usage
^^^^^^^^^^^^^^^^^
.. code-block:: java
import static akka.actor.Actors.*;
RegistrationService actor = remote().typedActorFor(RegistrationService.class, "user-service", 5000L, "localhost", 2552);
actor.registerUser(...);
There are variations on the 'remote()#typedActorFor' method. Here are some of them:
.. code-block:: java
... = remote().typedActorFor(interfaceClazz, serviceIdOrClassName, hostname, port);
... = remote().typedActorFor(interfaceClazz, serviceIdOrClassName, timeout, hostname, port);
... = remote().typedActorFor(interfaceClazz, serviceIdOrClassName, timeout, hostname, port, classLoader);
Data Compression Configuration
------------------------------
@ -493,44 +476,55 @@ You can configure it like this:
}
}
Code provisioning
-----------------
Akka does currently not support automatic code provisioning but requires you to have the remote actor class files available on both the "client" the "server" nodes.
This is something that will be addressed soon. Until then, sorry for the inconvenience.
Subscribe to Remote Client events
---------------------------------
Akka has a subscription API for remote client events. You can register an Actor as a listener and this actor will have to be able to process these events:
RemoteClientError { Throwable cause; RemoteClientModule client; InetSocketAddress remoteAddress; }
RemoteClientDisconnected { RemoteClientModule client; InetSocketAddress remoteAddress; }
RemoteClientConnected { RemoteClientModule client; InetSocketAddress remoteAddress; }
RemoteClientStarted { RemoteClientModule client; InetSocketAddress remoteAddress; }
RemoteClientShutdown { RemoteClientModule client; InetSocketAddress remoteAddress; }
RemoteClientWriteFailed { Object message; Throwable cause; RemoteClientModule client; InetSocketAddress remoteAddress; }
.. code-block:: java
class RemoteClientError { Throwable cause; RemoteClientModule client; InetSocketAddress remoteAddress; }
class RemoteClientDisconnected { RemoteClientModule client; InetSocketAddress remoteAddress; }
class RemoteClientConnected { RemoteClientModule client; InetSocketAddress remoteAddress; }
class RemoteClientStarted { RemoteClientModule client; InetSocketAddress remoteAddress; }
class RemoteClientShutdown { RemoteClientModule client; InetSocketAddress remoteAddress; }
class RemoteClientWriteFailed { Object message; Throwable cause; RemoteClientModule client; InetSocketAddress remoteAddress; }
So a simple listener actor can look like this:
.. code-block:: java
import akka.actor.UntypedActor;
import akka.remoteinterface.*;
class Listener extends UntypedActor {
public void onReceive(Object message) throws Exception {
if (message instanceof RemoteClientError) {
RemoteClientError event = (RemoteClientError)message;
Exception cause = event.getCause();
...
RemoteClientError event = (RemoteClientError) message;
Throwable cause = event.getCause();
// ...
} else if (message instanceof RemoteClientConnected) {
RemoteClientConnected event = (RemoteClientConnected)message;
...
RemoteClientConnected event = (RemoteClientConnected) message;
// ...
} else if (message instanceof RemoteClientDisconnected) {
RemoteClientDisconnected event = (RemoteClientDisconnected)message;
...
RemoteClientDisconnected event = (RemoteClientDisconnected) message;
// ...
} else if (message instanceof RemoteClientStarted) {
RemoteClientStarted event = (RemoteClientStarted)message;
...
RemoteClientStarted event = (RemoteClientStarted) message;
// ...
} else if (message instanceof RemoteClientShutdown) {
RemoteClientShutdown event = (RemoteClientShutdown)message;
...
RemoteClientShutdown event = (RemoteClientShutdown) message;
// ...
} else if (message instanceof RemoteClientWriteFailed) {
RemoteClientWriteFailed event = (RemoteClientWriteFailed)message;
...
RemoteClientWriteFailed event = (RemoteClientWriteFailed) message;
// ...
}
}
}
@ -550,43 +544,45 @@ Subscribe to Remote Server events
Akka has a subscription API for the server events. You can register an Actor as a listener and this actor will have to be able to process these events:
RemoteServerStarted { RemoteServerModule server; }
RemoteServerShutdown { RemoteServerModule server; }
RemoteServerError { Throwable cause; RemoteServerModule server; }
RemoteServerClientConnected { RemoteServerModule server; Option<InetSocketAddress> clientAddress; }
RemoteServerClientDisconnected { RemoteServerModule server; Option<InetSocketAddress> clientAddress; }
RemoteServerClientClosed { RemoteServerModule server; Option<InetSocketAddress> clientAddress; }
RemoteServerWriteFailed { Object request; Throwable cause; RemoteServerModule server; Option<InetSocketAddress> clientAddress; }
.. code-block:: java
class RemoteServerStarted { RemoteServerModule server; }
class RemoteServerShutdown { RemoteServerModule server; }
class RemoteServerError { Throwable cause; RemoteServerModule server; }
class RemoteServerClientConnected { RemoteServerModule server; Option<InetSocketAddress> clientAddress; }
class RemoteServerClientDisconnected { RemoteServerModule server; Option<InetSocketAddress> clientAddress; }
class RemoteServerClientClosed { RemoteServerModule server; Option<InetSocketAddress> clientAddress; }
class RemoteServerWriteFailed { Object request; Throwable cause; RemoteServerModule server; Option<InetSocketAddress> clientAddress; }
So a simple listener actor can look like this:
.. code-block:: java
import akka.actor.UntypedActor;
import akka.remoteinterface.*;
class Listener extends UntypedActor {
public void onReceive(Object message) throws Exception {
if (message instanceof RemoteServerError) {
RemoteServerError event = (RemoteServerError)message;
Exception cause = event.getCause();
...
} else if (message instanceof RemoteServerStarted) {
RemoteServerStarted event = (RemoteServerStarted)message;
...
} else if (message instanceof RemoteServerShutdown) {
RemoteServerShutdown event = (RemoteServerShutdown)message;
...
} else if (message instanceof RemoteServerClientConnected) {
RemoteServerClientConnected event = (RemoteServerClientConnected)message;
...
} else if (message instanceof RemoteServerClientDisconnected) {
RemoteServerClientDisconnected event = (RemoteServerClientDisconnected)message;
...
} else if (message instanceof RemoteServerClientClosed) {
RemoteServerClientClosed event = (RemoteServerClientClosed)message;
...
} else if (message instanceof RemoteServerWriteFailed) {
RemoteServerWriteFailed event = (RemoteServerWriteFailed)message;
...
if (message instanceof RemoteClientError) {
RemoteClientError event = (RemoteClientError) message;
Throwable cause = event.getCause();
// ...
} else if (message instanceof RemoteClientConnected) {
RemoteClientConnected event = (RemoteClientConnected) message;
// ...
} else if (message instanceof RemoteClientDisconnected) {
RemoteClientDisconnected event = (RemoteClientDisconnected) message;
// ...
} else if (message instanceof RemoteClientStarted) {
RemoteClientStarted event = (RemoteClientStarted) message;
// ...
} else if (message instanceof RemoteClientShutdown) {
RemoteClientShutdown event = (RemoteClientShutdown) message;
// ...
} else if (message instanceof RemoteClientWriteFailed) {
RemoteClientWriteFailed event = (RemoteClientWriteFailed) message;
// ...
}
}
}
@ -608,10 +604,27 @@ Message Serialization
All messages that are sent to remote actors needs to be serialized to binary format to be able to travel over the wire to the remote node. This is done by letting your messages extend one of the traits in the 'akka.serialization.Serializable' object. If the messages don't implement any specific serialization trait then the runtime will try to use standard Java serialization.
Read more about that in the `Serialization section <serialization-java>`_.
Here is one example, but full documentation can be found in the :ref:`serialization-java`.
Code provisioning
-----------------
Protobuf
^^^^^^^^
Akka does currently not support automatic code provisioning but requires you to have the remote actor class files available on both the "client" the "server" nodes.
This is something that will be addressed soon. Until then, sorry for the inconvenience.
Protobuf message specification needs to be compiled with 'protoc' compiler.
::
message ProtobufPOJO {
required uint64 id = 1;
required string name = 2;
required bool status = 3;
}
Using the generated message builder to send the message to a remote actor:
.. code-block:: java
actor.sendOneWay(ProtobufPOJO.newBuilder()
.setId(11)
.setStatus(true)
.setName("Coltrane")
.build());

View file

@ -1,38 +1,23 @@
.. _serialization-java:
Serialization (Java)
====================
Akka serialization module has been documented extensively under the Scala API section. In this section we will point out the different APIs that are available in Akka for Java based serialization of ActorRefs. The Scala APIs of ActorSerialization has implicit Format objects that set up the type class based serialization. In the Java API, the Format objects need to be specified explicitly.
.. sidebar:: Contents
Serialization of ActorRef
=========================
.. contents:: :local:
The following are the Java APIs for serialization of local ActorRefs:
.. code-block:: scala
/**
* Module for local actor serialization.
*/
object ActorSerialization {
// wrapper for implicits to be used by Java
def fromBinaryJ[T <: Actor](bytes: Array[Byte], format: Format[T]): ActorRef =
fromBinary(bytes)(format)
// wrapper for implicits to be used by Java
def toBinaryJ[T <: Actor](a: ActorRef, format: Format[T], srlMailBox: Boolean = true): Array[Byte] =
toBinary(a, srlMailBox)(format)
}
The following steps describe the procedure for serializing an Actor and ActorRef.
Akka serialization module has been documented extensively under the :ref:`serialization-scala` section. In this section we will point out the different APIs that are available in Akka for Java based serialization of ActorRefs. The Scala APIs of ActorSerialization has implicit Format objects that set up the type class based serialization. In the Java API, the Format objects need to be specified explicitly.
Serialization of a Stateless Actor
==================================
----------------------------------
Step 1: Define the Actor
------------------------
.. code-block:: scala
import akka.actor.UntypedActor;
public class SerializationTestActor extends UntypedActor {
public void onReceive(Object msg) {
getContext().replySafe("got it!");
@ -40,12 +25,13 @@ Step 1: Define the Actor
}
Step 2: Define the typeclass instance for the actor
---------------------------------------------------
Note how the generated Java classes are accessed using the $class based naming convention of the Scala compiler.
.. code-block:: scala
import akka.serialization.StatelessActorFormat;
class SerializationTestActorFormat implements StatelessActorFormat<SerializationTestActor> {
@Override
public SerializationTestActor fromBinary(byte[] bytes, SerializationTestActor act) {
@ -58,12 +44,20 @@ Note how the generated Java classes are accessed using the $class based naming c
}
}
**Step 3: Serialize and de-serialize**
Step 3: Serialize and de-serialize
The following JUnit snippet first creates an actor using the default constructor. The actor is, as we saw above a stateless one. Then it is serialized and de-serialized to get back the original actor. Being stateless, the de-serialized version behaves in the same way on a message as the original actor.
.. code-block:: java
import akka.actor.ActorRef;
import akka.actor.ActorTimeoutException;
import akka.actor.Actors;
import akka.actor.UntypedActor;
import akka.serialization.Format;
import akka.serialization.StatelessActorFormat;
import static akka.serialization.ActorSerialization.*;
@Test public void mustBeAbleToSerializeAfterCreateActorRefFromClass() {
ActorRef ref = Actors.actorOf(SerializationTestActor.class);
assertNotNull(ref);
@ -91,60 +85,69 @@ The following JUnit snippet first creates an actor using the default constructor
}
Serialization of a Stateful Actor
=================================
---------------------------------
Let's now have a look at how to serialize an actor that carries a state with it. Here the expectation is that the serialization of the actor will also persist the state information. And after de-serialization we will get back the state with which it was serialized.
Step 1: Define the Actor
------------------------
Here we consider an actor defined in Scala. We will however serialize using the Java APIs.
.. code-block:: scala
class MyUntypedActor extends UntypedActor {
var count = 0
def onReceive(message: Any): Unit = message match {
case m: String if m == "hello" =>
count = count + 1
getContext.replyUnsafe("world " + count)
case m: String =>
count = count + 1
getContext.replyUnsafe("hello " + m + " " + count)
case _ =>
throw new Exception("invalid message type")
import akka.actor.UntypedActor;
public class MyUntypedActor extends UntypedActor {
int count = 0;
public void onReceive(Object msg) {
if (msg.equals("hello")) {
count = count + 1;
getContext().replyUnsafe("world " + count);
} else if (msg instanceof String) {
count = count + 1;
getContext().replyUnsafe("hello " + msg + " " + count);
} else {
throw new IllegalArgumentException("invalid message type");
}
}
}
Note the actor has a state in the form of an Integer. And every message that the actor receives, it replies with an addition to the integer member.
Step 2: Define the instance of the typeclass
--------------------------------------------
.. code-block:: java
import akka.actor.UntypedActor;
import akka.serialization.Format;
import akka.serialization.SerializerFactory;
class MyUntypedActorFormat implements Format<MyUntypedActor> {
@Override
public MyUntypedActor fromBinary(byte[] bytes, MyUntypedActor act) {
ProtobufProtocol.Counter p =
(ProtobufProtocol.Counter) new SerializerFactory().getProtobuf().fromBinary(bytes, ProtobufProtocol.Counter.class);
act.count_$eq(p.getCount());
return act;
}
@Override
public byte[] toBinary(MyUntypedActor ac) {
return ProtobufProtocol.Counter.newBuilder().setCount(ac.count()).build().toByteArray();
}
@Override
public MyUntypedActor fromBinary(byte[] bytes, MyUntypedActor act) {
ProtobufProtocol.Counter p =
(ProtobufProtocol.Counter) new SerializerFactory().getProtobuf().fromBinary(bytes, ProtobufProtocol.Counter.class);
act.count = p.getCount();
return act;
}
Note the usage of Protocol Buffers to serialize the state of the actor.
@Override
public byte[] toBinary(MyUntypedActor ac) {
return ProtobufProtocol.Counter.newBuilder().setCount(ac.count()).build().toByteArray();
}
}
Note the usage of Protocol Buffers to serialize the state of the actor. ProtobufProtocol.Counter is something
you need to define yourself
Step 3: Serialize and de-serialize
----------------------------------
.. code-block:: java
import akka.actor.ActorRef;
import akka.actor.ActorTimeoutException;
import akka.actor.Actors;
import static akka.serialization.ActorSerialization.*;
@Test public void mustBeAbleToSerializeAStatefulActor() {
ActorRef ref = Actors.actorOf(MyUntypedActor.class);
assertNotNull(ref);

View file

@ -1,10 +1,14 @@
Software Transactional Memory (Java)
====================================
.. sidebar:: Contents
.. contents:: :local:
Module stability: **SOLID**
Overview of STM
===============
---------------
An `STM <http://en.wikipedia.org/wiki/Software_transactional_memory>`_ turns the Java heap into a transactional data set with begin/commit/rollback semantics. Very much like a regular database. It implements the first three letters in ACID; ACI:
* (failure) Atomicity: all changes during the execution of a transaction make it, or none make it. This only counts for transactional datastructures.
@ -24,7 +28,7 @@ The STM is based on Transactional References (referred to as Refs). Refs are mem
Working with immutable collections can sometimes give bad performance due to extensive copying. Scala provides so-called persistent datastructures which makes working with immutable collections fast. They are immutable but with constant time access and modification. The use of structural sharing and an insert or update does not ruin the old structure, hence “persistent”. Makes working with immutable composite types fast. The persistent datastructures currently consist of a Map and Vector.
Simple example
==============
--------------
Here is a simple example of an incremental counter using STM. This shows creating a ``Ref``, a transactional reference, and then modifying it within a transaction, which is delimited by an ``Atomic`` anonymous inner class.
@ -50,15 +54,14 @@ Here is a simple example of an incremental counter using STM. This shows creatin
counter();
// -> 2
----
Ref
===
---
Refs (transactional references) are mutable references to values and through the STM allow the safe sharing of mutable data. To ensure safety the value stored in a Ref should be immutable. The value referenced by a Ref can only be accessed or swapped within a transaction. Refs separate identity from value.
Creating a Ref
--------------
^^^^^^^^^^^^^^
You can create a Ref with or without an initial value.
@ -73,7 +76,7 @@ You can create a Ref with or without an initial value.
final Ref<Integer> ref = new Ref<Integer>();
Accessing the value of a Ref
----------------------------
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Use ``get`` to access the value of a Ref. Note that if no initial value has been given then the value is initially ``null``.
@ -91,7 +94,7 @@ Use ``get`` to access the value of a Ref. Note that if no initial value has been
// -> value = 0
Changing the value of a Ref
---------------------------
^^^^^^^^^^^^^^^^^^^^^^^^^^^
To set a new value for a Ref you can use ``set`` (or equivalently ``swap``), which sets the new value and returns the old value.
@ -107,10 +110,9 @@ To set a new value for a Ref you can use ``set`` (or equivalently ``swap``), whi
}
}.execute();
----
Transactions
============
------------
A transaction is delimited using an ``Atomic`` anonymous inner class.
@ -125,24 +127,24 @@ A transaction is delimited using an ``Atomic`` anonymous inner class.
All changes made to transactional objects are isolated from other changes, all make it or non make it (so failure atomicity) and are consistent. With the AkkaSTM you automatically have the Oracle version of the SERIALIZED isolation level, lower isolation is not possible. To make it fully serialized, set the writeskew property that checks if a writeskew problem is allowed to happen.
Retries
-------
^^^^^^^
A transaction is automatically retried when it runs into some read or write conflict, until the operation completes, an exception (throwable) is thrown or when there are too many retries. When a read or writeconflict is encountered, the transaction uses a bounded exponential backoff to prevent cause more contention and give other transactions some room to complete.
If you are using non transactional resources in an atomic block, there could be problems because a transaction can be retried. If you are using print statements or logging, it could be that they are called more than once. So you need to be prepared to deal with this. One of the possible solutions is to work with a deferred or compensating task that is executed after the transaction aborts or commits.
Unexpected retries
------------------
^^^^^^^^^^^^^^^^^^
It can happen for the first few executions that you get a few failures of execution that lead to unexpected retries, even though there is not any read or writeconflict. The cause of this is that speculative transaction configuration/selection is used. There are transactions optimized for a single transactional object, for 1..n and for n to unlimited. So based on the execution of the transaction, the system learns; it begins with a cheap one and upgrades to more expensive ones. Once it has learned, it will reuse this knowledge. It can be activated/deactivated using the speculative property on the TransactionFactoryBuilder. In most cases it is best use the default value (enabled) so you get more out of performance.
Coordinated transactions and Transactors
----------------------------------------
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
If you need coordinated transactions across actors or threads then see `Transactors <transactors-java>`_.
If you need coordinated transactions across actors or threads then see :ref:`transactors-java`.
Configuring transactions
------------------------
^^^^^^^^^^^^^^^^^^^^^^^^
It's possible to configure transactions. The ``Atomic`` class can take a ``TransactionFactory``, which can determine properties of the transaction. A default transaction factory is used if none is specified. You can create a ``TransactionFactory`` with a ``TransactionFactoryBuilder``.
@ -197,7 +199,7 @@ You can also specify the default values for some of these options in akka.conf.
}
Transaction lifecycle listeners
-------------------------------
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
It's possible to have code that will only run on the successful commit of a transaction, or when a transaction aborts. You can do this by adding ``deferred`` or ``compensating`` blocks to a transaction.
@ -225,7 +227,7 @@ It's possible to have code that will only run on the successful commit of a tran
}.execute();
Blocking transactions
---------------------
^^^^^^^^^^^^^^^^^^^^^
You can block in a transaction until a condition is met by using an explicit ``retry``. To use ``retry`` you also need to configure the transaction to allow explicit retries.
@ -338,7 +340,7 @@ Here is an example of using ``retry`` to block until an account has enough money
}
Alternative blocking transactions
---------------------------------
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
You can also have two alternative blocking transactions, one of which can succeed first, with ``EitherOrElse``.
@ -443,10 +445,9 @@ You can also have two alternative blocking transactions, one of which can succee
}
}
----
Transactional datastructures
============================
----------------------------
Akka provides two datastructures that are managed by the STM.
@ -510,26 +511,24 @@ Here is an example of creating and accessing a TransactionalVector:
}
}.execute();
----
Persistent datastructures
=========================
-------------------------
Akka's STM should only be used with immutable data. This can be costly if you have large datastructures and are using a naive copy-on-write. In order to make working with immutable datastructures fast enough Scala provides what are called Persistent Datastructures. There are currently two different ones:
- HashMap (`scaladoc <http://www.scala-lang.org/api/current/scala/collection/immutable/HashMap.html>`_)
- Vector (`scaladoc <http://www.scala-lang.org/api/current/scala/collection/immutable/Vector.html>`_)
- HashMap (`scaladoc <http://www.scala-lang.org/api/current/scala/collection/immutable/HashMap.html>`__)
- Vector (`scaladoc <http://www.scala-lang.org/api/current/scala/collection/immutable/Vector.html>`__)
They are immutable and each update creates a completely new version but they are using clever structural sharing in order to make them almost as fast, for both read and update, as regular mutable datastructures.
This illustration is taken from Rich Hickey's presentation. Copyright Rich Hickey 2009.
.. image:: http://eclipsesource.com/blogs/wp-content/uploads/2009/12/clojure-trees.png
.. image:: ../images/clojure-trees.png
----
JTA integration
===============
---------------
The STM has JTA (Java Transaction API) integration. This means that it will, if enabled, hook in to JTA and start a JTA transaction when the STM transaction is started. It will also rollback the STM transaction if the JTA transaction has failed and vice versa. This does not mean that the STM is made durable, if you need that you should use one of the `persistence modules <persistence>`_. It simply means that the STM will participate and interact with and external JTA provider, for example send a message using JMS atomically within an STM transaction, or use Hibernate to persist STM managed data etc.
@ -555,4 +554,4 @@ You also have to configure which JTA provider to use etc in the 'jta' config sec
timeout = 60
}
----

View file

@ -1,10 +1,16 @@
**<span style="font-size: 150%;">Transactors (Java)</span>**
============================================================
.. _transactors-java:
Transactors (Java)
==================
.. sidebar:: Contents
.. contents:: :local:
Module stability: **SOLID**
Why Transactors?
================
----------------
Actors are excellent for solving problems where you have many independent processes that can work in isolation and only interact with other Actors through message passing. This model fits many problems. But the actor model is unfortunately a terrible model for implementing truly shared state. E.g. when you need to have consensus and a stable view of state across many components. The classic example is the bank account where clients can deposit and withdraw, in which each operation needs to be atomic. For detailed discussion on the topic see `this JavaOne presentation <http://www.slideshare.net/jboner/state-youre-doing-it-wrong-javaone-2009>`_.
@ -15,21 +21,21 @@ Akka's Transactors combine Actors and STM to provide the best of the Actor model
If you need Durability then you should not use one of the in-memory data structures but one of the persistent ones.
Generally, the STM is not needed very often when working with Akka. Some use-cases (that we can think of) are:
# When you really need composable message flows across many actors updating their **internal local** state but need them to do that atomically in one big transaction. Might not often, but when you do need this then you are screwed without it.
# When you want to share a datastructure across actors.
# When you need to use the persistence modules.
- When you really need composable message flows across many actors updating their **internal local** state but need them to do that atomically in one big transaction. Might not often, but when you do need this then you are screwed without it.
- When you want to share a datastructure across actors.
- When you need to use the persistence modules.
Actors and STM
--------------
^^^^^^^^^^^^^^
You can combine Actors and STM in several ways. An Actor may use STM internally so that particular changes are guaranteed to be atomic. Actors may also share transactional datastructures as the STM provides safe shared state across threads.
It's also possible to coordinate transactions across Actors or threads so that either the transactions in a set all commit successfully or they all fail. This is the focus of Transactors and the explicit support for coordinated transactions in this section.
----
Coordinated transactions
========================
------------------------
Akka provides an explicit mechanism for coordinating transactions across actors. Under the hood it uses a ``CountDownCommitBarrier``, similar to a CountDownLatch.
@ -40,9 +46,11 @@ Here is an example of coordinating two simple counter UntypedActors so that they
import akka.actor.ActorRef;
public class Increment {
private ActorRef friend = null;
private final ActorRef friend;
public Increment() {}
public Increment() {
this.friend = null;
}
public Increment(ActorRef friend) {
this.friend = friend;
@ -59,9 +67,7 @@ Here is an example of coordinating two simple counter UntypedActors so that they
.. code-block:: java
import akka.actor.ActorRef;
import akka.actor.UntypedActor;
import static akka.actor.Actors.*;
import akka.stm.Ref;
import akka.transactor.Atomically;
import akka.transactor.Coordinated;
@ -88,11 +94,8 @@ Here is an example of coordinating two simple counter UntypedActors so that they
}
});
}
} else if (incoming instanceof String) {
String message = (String) incoming;
if (message.equals("GetCount")) {
getContext().replyUnsafe(count.get());
}
} else if (incoming.equals("GetCount")) {
getContext().replyUnsafe(count.get());
}
}
}
@ -104,7 +107,7 @@ Here is an example of coordinating two simple counter UntypedActors so that they
counter1.sendOneWay(new Coordinated(new Increment(counter2)));
To start a new coordinated transaction set that you will also participate in, just create a ``Coordinated`` object:
To start a new coordinated transaction that you will also participate in, just create a ``Coordinated`` object:
.. code-block:: java
@ -116,7 +119,7 @@ To start a coordinated transaction that you won't participate in yourself you ca
actor.sendOneWay(new Coordinated(new Message()));
To include another actor in the same coordinated transaction set that you've created or received, use the ``coordinate`` method on that object. This will increment the number of parties involved by one and create a new ``Coordinated`` object to be sent.
To include another actor in the same coordinated transaction that you've created or received, use the ``coordinate`` method on that object. This will increment the number of parties involved by one and create a new ``Coordinated`` object to be sent.
.. code-block:: java
@ -134,10 +137,9 @@ To enter the coordinated transaction use the atomic method of the coordinated ob
The coordinated transaction will wait for the other transactions before committing. If any of the coordinated transactions fail then they all fail.
----
UntypedTransactor
=================
-----------------
UntypedTransactors are untyped actors that provide a general pattern for coordinating transactions, using the explicit coordination described above.
@ -146,10 +148,12 @@ Here's an example of a simple untyped transactor that will join a coordinated tr
.. code-block:: java
import akka.transactor.UntypedTransactor;
import akka.stm.Ref;
public class Counter extends UntypedTransactor {
Ref<Integer> count = new Ref<Integer>(0);
@Override
public void atomically(Object message) {
if (message instanceof Increment) {
count.set(count.get() + 1);
@ -174,7 +178,8 @@ Example of coordinating an increment, similar to the explicitly coordinated exam
public class Counter extends UntypedTransactor {
Ref<Integer> count = new Ref<Integer>(0);
@Override public Set<SendTo> coordinate(Object message) {
@Override
public Set<SendTo> coordinate(Object message) {
if (message instanceof Increment) {
Increment increment = (Increment) message;
if (increment.hasFriend())
@ -183,6 +188,7 @@ Example of coordinating an increment, similar to the explicitly coordinated exam
return nobody();
}
@Override
public void atomically(Object message) {
if (message instanceof Increment) {
count.set(count.get() + 1);
@ -190,14 +196,13 @@ Example of coordinating an increment, similar to the explicitly coordinated exam
}
}
To execute directly before or after the coordinated transaction, override the ``before`` and ``after`` methods. These methods also expect partial functions like the receive method. They do not execute within the transaction.
To execute directly before or after the coordinated transaction, override the ``before`` and ``after`` methods. They do not execute within the transaction.
To completely bypass coordinated transactions override the ``normally`` method. Any message matched by ``normally`` will not be matched by the other methods, and will not be involved in coordinated transactions. In this method you can implement normal actor behavior, or use the normal STM atomic for local transactions.
----
Coordinating Typed Actors
=========================
-------------------------
It's also possible to use coordinated transactions with typed actors. You can explicitly pass around ``Coordinated`` objects, or use built-in support with the ``@Coordinated`` annotation and the ``Coordination.coordinate`` method.
@ -249,17 +254,18 @@ Here's an example of using ``@Coordinated`` with a TypedActor to coordinate incr
}
}
`<code format="java">`_
Counter counter1 = (Counter) TypedActor.newInstance(Counter.class, CounterImpl.class);
Counter counter2 = (Counter) TypedActor.newInstance(Counter.class, CounterImpl.class);
.. code-block:: java
Coordination.coordinate(true, new Atomically() {
Counter counter1 = (Counter) TypedActor.newInstance(Counter.class, CounterImpl.class);
Counter counter2 = (Counter) TypedActor.newInstance(Counter.class, CounterImpl.class);
Coordination.coordinate(true, new Atomically() {
public void atomically() {
counter1.increment();
counter2.increment();
counter1.increment();
counter2.increment();
}
});
});
TypedActor.stop(counter1);
TypedActor.stop(counter2);
TypedActor.stop(counter1);
TypedActor.stop(counter2);
`<code>`_

View file

@ -1,6 +1,10 @@
Typed Actors (Java)
===================
.. sidebar:: Contents
.. contents:: :local:
Module stability: **SOLID**
The Typed Actors are implemented through `Typed Actors <http://en.wikipedia.org/wiki/Active_object>`_. It uses AOP through `AspectWerkz <http://aspectwerkz.codehaus.org/>`_ to turn regular POJOs into asynchronous non-blocking Actors with semantics of the Actor Model. E.g. each message dispatch is turned into a message that is put on a queue to be processed by the Typed Actor sequentially one by one.
@ -171,7 +175,7 @@ Here is an example how you can use it to in a 'void' (e.g. fire-forget) method t
}
}
If the sender, sender future etc. is not available, then these methods will return 'null' so you should have a way of dealing with scenario.
If the sender, sender future etc. is not available, then these methods will return 'null' so you should have a way of dealing with that scenario.
Messages and immutability
-------------------------

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@ -1,7 +1,9 @@
Actors (Java)
=============
=
.. sidebar:: Contents
.. contents:: :local:
Module stability: **SOLID**
@ -16,11 +18,15 @@ Here is an example:
.. code-block:: java
import akka.actor.UntypedActor;
import akka.event.EventHandler;
public class SampleUntypedActor extends UntypedActor {
public void onReceive(Object message) throws Exception {
if (message instanceof String)
EventHandler.info(this, String.format("Received String message: %s", message));
EventHandler.info(this, String.format("Received String message: %s",
message));
else
throw new IllegalArgumentException("Unknown message: " + message);
}
@ -409,8 +415,9 @@ Actor life-cycle
The actor has a well-defined non-circular life-cycle.
`<code>`_
NEW (newly created actor) - can't receive messages (yet)
=> STARTED (when 'start' is invoked) - can receive messages
=> SHUT DOWN (when 'exit' or 'stop' is invoked) - can't do anything
`<code>`_
::
NEW (newly created actor) - can't receive messages (yet)
=> STARTED (when 'start' is invoked) - can receive messages
=> SHUT DOWN (when 'exit' or 'stop' is invoked) - can't do anything

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@ -1,60 +0,0 @@
Akka
====
**Simpler Scalability, Fault-Tolerance, Concurrency & Remoting through Actors**
We believe that writing correct concurrent, fault-tolerant and scalable applications is too hard. Most of the time it's because we are using the wrong tools and the wrong level of abstraction. Akka is here to change that. Using the Actor Model together with Software Transactional Memory we raise the abstraction level and provide a better platform to build correct concurrent and scalable applications. For fault-tolerance we adopt the "Let it crash" / "Embrace failure" model which have been used with great success in the telecom industry to build applications that self-heals, systems that never stop. Actors also provides the abstraction for transparent distribution and the basis for truly scalable and fault-tolerant applications. Akka is Open Source and available under the Apache 2 License.
Akka is split up into two different parts:
* Akka - Reflects all the sections under 'Scala API' and 'Java API' in the navigation bar.
* Akka Modules - Reflects all the sections under 'Add-on modules' in the navigation bar.
Download from `<http://akka.io/downloads/>`_
News: Akka 1.0 final is released
--------------------------------
1.0 documentation
-----------------
This documentation covers the latest release ready code in 'master' branch in the repository.
If you want the documentation for the 1.0 release you can find it `here <http://akka.io/docs/akka-1.0/space.menu.html>`_.
You can watch the recording of the `Akka talk at JFokus in Feb 2011 <http://79.136.112.58/ability/show/xaimkwdli/a2_20110216_1110/mainshow.asp?STREAMID=1>`_.
`<media type="custom" key="8924178">`_
**Akka implements a unique hybrid of:**
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
* `Actors <untyped-actors-java>`_, which gives you:
* Simple and high-level abstractions for concurrency and parallelism.
* Asynchronous, non-blocking and highly performant event-driven programming model.
* Very lightweight event-driven processes (create ~6.5 million actors on 4 G RAM).
* `Failure management <fault-tolerance-java>`_ through supervisor hierarchies with `let-it-crash <http://letitcrash.com>`_ semantics. Excellent for writing highly fault-tolerant systems that never stop, systems that self-heal.
* `Software Transactional Memory <stm-java>`_ (STM). (Distributed transactions coming soon).
* `Transactors <transactors-java>`_: combine actors and STM into transactional actors. Allows you to compose atomic message flows with automatic retry and rollback.
* `Remote actors <remote-actors-java>`_: highly performant distributed actors with remote supervision and error management.
* Java and Scala API.
**Akka also has a set of add-on modules:**
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
* `Camel <camel>`_: Expose actors as Apache Camel endpoints.
* `Spring <spring-integration>`_: Wire up typed actors in the Spring config using Akka's namespace.
* `REST <rest>`_ (JAX-RS): Expose actors as REST services.
* `OSGi <osgi>`_: Akka and all its dependency is OSGi enabled.
* `Mist <http#Mist%20-%20Lightweight%20Asynchronous%20HTTP>`_: Expose actors as asynchronous HTTP services.
* `Security <security>`_: Basic, Digest and Kerberos based security.
* `Microkernel <microkernel>`_: Run Akka as a stand-alone self-hosted kernel.
* `FSM <fsm-scala>`_: Finite State Machine support.
* `JTA <jta>`_: Let the STM interoperate with other transactional resources.
* `Pub/Sub <pubsub>`_: Publish-Subscribe across remote nodes.
**Akka can be used in two different ways:**
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
* As a library: used by a web app, to be put into WEB-INF/lib or as a regular JAR on your classpath.
* As a microkernel: stand-alone kernel, embedding a servlet container and all the other modules.
See the `Use-case and Deployment Scenarios <deployment-scenarios>`_ for details.

View file

@ -316,7 +316,7 @@ Supervised actors have the option to reply to the initial sender within preResta
self.reply_?(reason.getMessage)
}
override def postStop {
override def postStop() {
self.reply_?("stopped by supervisor")
}
}

View file

@ -269,7 +269,7 @@ Finally, bind the *handleHttpRequest* function of the *Endpoint* trait to the ac
//
// this is where you want attach your endpoint hooks
//
override def preStart = {
override def preStart() = {
//
// we expect there to be one root and that it's already been started up
// obviously there are plenty of other ways to obtaining this actor
@ -397,7 +397,7 @@ As noted above, hook functions are non-exclusive. This means multiple actors can
//
// this is where you want attach your endpoint hooks
//
override def preStart = {
override def preStart() = {
//
// we expect there to be one root and that it's already been started up
// obviously there are plenty of other ways to obtaining this actor

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@ -1,51 +0,0 @@
Issue Tracking
==============
Akka is using Assembla as issue tracking system.
Browsing
--------
You can find the Akka tickets here: `<http://www.assembla.com/spaces/akka>`_
You can find the Akka Modules tickets here: `<https://www.assembla.com/spaces/akka-modules/tickets>`_
The roadmap for each milestone is here: `<https://www.assembla.com/spaces/akka/milestones>`_
Creating tickets
----------------
In order to create tickets you need to do the following:
# Register here: `<https://www.assembla.com/user/signup>`_
# Log in
For Akka tickets:
# Create the ticket: `<https://www.assembla.com/spaces/akka/tickets/new>`_
For Akka Modules tickets:
# Create the ticket: `<https://www.assembla.com/spaces/akka-modules/tickets>`_
Thanks a lot for reporting bugs and suggesting features.
Failing test
------------
Please submit a failing test on the following format:
`<code format="scala">`_
import org.scalatest.WordSpec
import org.scalatest.matchers.MustMatchers
class Ticket001Spec extends WordSpec with MustMatchers {
"An XXX" should {
"do YYY" in {
1 must be (1)
}
}
}
`<code>`_

View file

@ -1,432 +0,0 @@
Migration guide from 0.10.x to 1.0.x
====================================
----
Akka & Akka Modules separated into two different repositories and distributions
-------------------------------------------------------------------------------
Akka is split up into two different parts:
* Akka - Reflects all the sections under 'Scala API' and 'Java API' in the navigation bar.
* Akka Modules - Reflects all the sections under 'Add-on modules' in the navigation bar.
Download the release you need (Akka core or Akka Modules) from `<http://akka.io/downloads>`_ and unzip it.
----
Changed Akka URI
----------------
http:*akkasource.org changed to http:*akka.io
Reflects XSDs, Maven repositories, ScalaDoc etc.
----
Removed 'se.scalablesolutions' prefix
-------------------------------------
We have removed some boilerplate by shortening the Akka package from
**se.scalablesolutions.akka** to just **akka** so just do a search-replace in your project,
we apologize for the inconvenience, but we did it for our users.
----
Akka-core is no more
--------------------
Akka-core has been split into akka-actor, akka-stm, akka-typed-actor & akka-remote this means that you need to update any deps you have on akka-core.
----
Config
------
Turning on/off modules
^^^^^^^^^^^^^^^^^^^^^^
All the 'service = on' elements for turning modules on and off have been replaced by a top-level list of the enabled services.
Services available for turning on/off are:
* "remote"
* "http"
* "camel"
**All** services are **OFF** by default. Enable the ones you are using.
.. code-block:: ruby
akka {
enabled-modules = [] # Comma separated list of the enabled modules. Options: ["remote", "camel", "http"]
}
Renames
^^^^^^^
* 'rest' section - has been renamed to 'http' to align with the module name 'akka-http'.
* 'storage' section - has been renamed to 'persistence' to align with the module name 'akka-persistence'.
.. code-block:: ruby
akka {
http {
..
}
persistence {
..
}
}
----
Important changes from RC2-RC3
------------------------------
**akka.config.SupervisionSupervise**
def apply(actorRef: ActorRef, lifeCycle: LifeCycle, registerAsRemoteService: Boolean = false)
- boolean instead of remoteAddress, registers that actor with it's id as service name on the local server
**akka.actor.Actors now is the API for Java to interact with Actors, Remoting and ActorRegistry:**
import static akka.actor.Actors.*;
*actorOf()..*
remote().actorOf()...
*registry().actorsFor("foo")...*
***akka.actor.Actor now is the API for Scala to interact with Actors, Remoting and ActorRegistry:***
*import akka.actor.Actor._*
actorOf()...
*remote.actorOf()...*
registry.actorsFor("foo")
**object UntypedActor has been deleted and replaced with akka.actor.Actors/akka.actor.Actor (Java/Scala)**
UntypedActor.actorOf -> Actors.actorOf (Java) or Actor.actorOf (Scala)
**object ActorRegistry has been deleted and replaced with akka.actor.Actors.registry()/akka.actor.Actor.registry (Java/Scala)**
ActorRegistry. -> Actors.registry(). (Java) or Actor.registry. (Scala)
**object RemoteClient has been deleted and replaced with akka.actor.Actors.remote()/akka.actor.Actor.remote (Java/Scala)**
RemoteClient -> Actors.remote() (Java) or Actor.remote (Scala)
**object RemoteServer has been deleted and replaced with akka.actor.Actors.remote()/akka.actor.Actor.remote (Java/Scala)**
RemoteServer - deleted -> Actors.remote() (Java) or Actor.remote (Scala)
**classes RemoteActor, RemoteUntypedActor and RemoteUntypedConsumerActors has been deleted and replaced**
**with akka.actor.Actors.remote().actorOf(x, host port)/akka.actor.Actor.remote.actorOf(x, host, port)**
RemoteActor, RemoteUntypedActor - deleted, use: remote().actorOf(YourActor.class, host, port) (Java) or remote.actorOf[YourActor](host, port)
**Remoted spring-actors now default to spring id as service-name, use "service-name" attribute on "remote"-tag to override**
**Listeners for RemoteServer and RemoteClient** are now registered on Actors.remote().addListener (Java) or Actor.remote.addListener (Scala),
this means that all listeners get all remote events, both remote server evens and remote client events, **so adjust your code accordingly.**
**ActorRef.startLinkRemote has been removed since one specified on creation wether the actor is client-managed or not.**
Important change from RC3 to RC4
--------------------------------
The Akka-Spring namespace has changed from akkasource.org and scalablesolutions.se to http:*akka.io/schema and http:*akka.io/akka-<version>.xsd
----
Module akka-actor
-----------------
The Actor.init callback has been renamed to "preStart" to align with the general callback naming and is more clear about when it's called.
The Actor.shutdown callback has been renamed to "postStop" to align with the general callback naming and is more clear about when it's called.
The Actor.initTransactionalState callback has been removed, logic should be moved to preStart and be wrapped in an atomic block
**se.scalablesolutions.akka.config.ScalaConfig** and **se.scalablesolutions.akka.config.JavaConfig** have been merged into **akka.config.Supervision**
**RemoteAddress** has moved from **se.scalablesolutions.akka.config.ScalaConfig** to **akka.config**
The ActorRef.lifeCycle has changed signature from Option[LifeCycle] to LifeCycle, this means you need to change code that looks like this:
**self.lifeCycle = Some(LifeCycle(Permanent))** to **self.lifeCycle = Permanent**
The equivalent to **self.lifeCycle = None** is **self.lifeCycle = UndefinedLifeCycle**
**LifeCycle(Permanent)** becomes **Permanent**
**new LifeCycle(permanent())** becomes **permanent()** (need to do: import static se.scalablesolutions.akka.config.Supervision.*; first)
**JavaConfig.Component** and **ScalaConfig.Component** have been consolidated and renamed as **Supervision.SuperviseTypedActor**
**self.trapExit** has been moved into the FaultHandlingStrategy, and **ActorRef.faultHandler** has switched type from Option[FaultHandlingStrategy]
to FaultHandlingStrategy:
|| **Scala** ||
||
`<code format="scala">`_
import akka.config.Supervision._
self.faultHandler = OneForOneStrategy(List(classOf[Exception]), 3, 5000)
`<code>`_ ||
|| **Java** ||
||
`<code format="java">`_
import static akka.Supervision.*;
getContext().setFaultHandler(new OneForOneStrategy(new Class[] { Exception.class },50,1000))
`<code>`_ ||
**RestartStrategy, AllForOne, OneForOne** have been replaced with **AllForOneStrategy** and **OneForOneStrategy** in **se.scalablesolutions.akka.config.Supervision**
|| **Scala** ||
||
`<code format="scala">`_
import akka.config.Supervision._
SupervisorConfig(
OneForOneStrategy(List(classOf[Exception]), 3, 5000),
Supervise(pingpong1,Permanent) :: Nil
)
`<code>`_ ||
|| **Java** ||
||
`<code format="java">`_
import static akka.Supervision.*;
new SupervisorConfig(
new OneForOneStrategy(new Class[] { Exception.class },50,1000),
new Server[] { new Supervise(pingpong1, permanent()) }
)
`<code>`_ ||
We have removed the following factory methods:
**Actor.actor { case foo => bar }**
**Actor.transactor { case foo => bar }**
**Actor.temporaryActor { case foo => bar }**
**Actor.init {} receive { case foo => bar }**
They started the actor and no config was possible, it was inconsistent and irreparable.
replace with your own factories, or:
**actorOf( new Actor { def receive = { case foo => bar } } ).start**
**actorOf( new Actor { self.lifeCycle = Temporary; def receive = { case foo => bar } } ).start**
ReceiveTimeout is now rescheduled after every message, before there was only an initial timeout.
To stop rescheduling of ReceiveTimeout, set **receiveTimeout = None**
HotSwap
-------
HotSwap does no longer use behavior stacking by default, but that is an option to both "become" and HotSwap.
HotSwap now takes for Scala a Function from ActorRef to a Receive, the ActorRef passed in is the reference to self, so you can do self.reply() etc.
----
Module akka-stm
---------------
The STM stuff is now in its own module. This means that there is no support for transactions or transactors in akka-actor.
Local and global
^^^^^^^^^^^^^^^^
The **local/global** distinction has been dropped. This means that if the following general import was being used:
.. code-block:: scala
import akka.stm.local._
this is now just:
.. code-block:: scala
import akka.stm._
Coordinated is the new global
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
There is a new explicit mechanism for coordinated transactions. See the `Scala Transactors <transactors-scala>`_ and `Java Transactors <transactors-java>`_ documentation for more information. Coordinated transactions and transactors are found in the ``akka.transactor`` package now. The usage of transactors has changed.
Agents
^^^^^^
Agent is now in the akka-stm module and has moved to the ``akka.agent`` package. The implementation has been reworked and is now closer to Clojure agents. There is not much difference in general usage, the main changes involve interaction with the STM.
While updates to Agents are asynchronous, the state of an Agent is always immediately available for reading by any thread. Agents are integrated with the STM - any dispatches made in a transaction are held until that transaction commits, and are discarded if it is retried or aborted. There is a new ``sendOff`` method for long-running or blocking update functions.
----
Module akka-camel
-----------------
Access to the CamelService managed by CamelServiceManager has changed:
* Method service renamed to mandatoryService (Scala)
* Method service now returns Option[CamelService] (Scala)
* Introduced method getMandatoryService() (Java)
* Introduced method getService() (Java)
|| **Scala** ||
||
`<code format="scala">`_
import se.scalablesolutions.akka.camel.CamelServiceManager._
import se.scalablesolutions.akka.camel.CamelService
val o: Option[CamelService] = service
val s: CamelService = mandatoryService
`<code>`_ ||
|| **Java** ||
||
`<code format="java">`_
import se.scalablesolutions.akka.camel.CamelService;
import se.scalablesolutions.akka.japi.Option;
import static se.scalablesolutions.akka.camel.CamelServiceManager.*;
Option<CamelService> o = getService();
CamelService s = getMandatoryService();
`<code>`_ ||
Access to the CamelContext and ProducerTemplate managed by CamelContextManager has changed:
* Method context renamed to mandatoryContext (Scala)
* Method template renamed to mandatoryTemplate (Scala)
* Method service now returns Option[CamelContext] (Scala)
* Method template now returns Option[ProducerTemplate] (Scala)
* Introduced method getMandatoryContext() (Java)
* Introduced method getContext() (Java)
* Introduced method getMandatoryTemplate() (Java)
* Introduced method getTemplate() (Java)
|| **Scala** ||
||
`<code format="scala">`_
import org.apache.camel.CamelContext
import org.apache.camel.ProducerTemplate
import se.scalablesolutions.akka.camel.CamelContextManager._
val co: Option[CamelContext] = context
val to: Option[ProducerTemplate] = template
val c: CamelContext = mandatoryContext
val t: ProducerTemplate = mandatoryTemplate
`<code>`_ ||
|| **Java** ||
||
`<code format="java">`_
import org.apache.camel.CamelContext;
import org.apache.camel.ProducerTemplate;
import se.scalablesolutions.akka.japi.Option;
import static se.scalablesolutions.akka.camel.CamelContextManager.*;
Option<CamelContext> co = getContext();
Option<ProducerTemplate> to = getTemplate();
CamelContext c = getMandatoryContext();
ProducerTemplate t = getMandatoryTemplate();
`<code>`_ ||
The following methods have been renamed on class se.scalablesolutions.akka.camel.Message:
* bodyAs(Class) has been renamed to getBodyAs(Class)
* headerAs(String, Class) has been renamed to getHeaderAs(String, Class)
The API for waiting for consumer endpoint activation and de-activation has been changed
* CamelService.expectEndpointActivationCount has been removed and replaced by CamelService.awaitEndpointActivation
* CamelService.expectEndpointDeactivationCount has been removed and replaced by CamelService.awaitEndpointDeactivation
|| **Scala** ||
||
`<code format="scala">`_
import se.scalablesolutions.akka.actor.Actor
import se.scalablesolutions.akka.camel.CamelServiceManager._
val s = startCamelService
val actor = Actor.actorOf[SampleConsumer]
// wait for 1 consumer being activated
s.awaitEndpointActivation(1) {
actor.start
}
// wait for 1 consumer being de-activated
s.awaitEndpointDeactivation(1) {
actor.stop
}
s.stop
`<code>`_ ||
|| **Java** ||
||
`<code format="java">`_
import java.util.concurrent.TimeUnit;
import se.scalablesolutions.akka.actor.ActorRef;
import se.scalablesolutions.akka.actor.Actors;
import se.scalablesolutions.akka.camel.CamelService;
import se.scalablesolutions.akka.japi.SideEffect;
import static se.scalablesolutions.akka.camel.CamelServiceManager.*;
CamelService s = startCamelService();
final ActorRef actor = Actors.actorOf(SampleUntypedConsumer.class);
// wait for 1 consumer being activated
s.awaitEndpointActivation(1, new SideEffect() {
public void apply() {
actor.start();
}
});
// wait for 1 consumer being de-activated
s.awaitEndpointDeactivation(1, new SideEffect() {
public void apply() {
actor.stop();
}
});
s.stop();
`<code>`_ ||
-
Module Akka-Http
----------------
Atmosphere support has been removed. If you were using akka.comet.AkkaServlet for Jersey support only,
you can switch that to: akka.http.AkkaRestServlet and it should work just like before.
Atmosphere has been removed because we have a new async http support in the form of Akka Mist, a very thin bridge
between Servlet3.0/JettyContinuations and Actors, enabling Http-as-messages, read more about it here:
http://doc.akka.io/http#Mist%20-%20Lightweight%20Asynchronous%20HTTP
If you really need Atmosphere support, you can add it yourself by following the steps listed at the start of:
http://doc.akka.io/comet
Module akka-spring
------------------
The Akka XML schema URI has changed to http://akka.io/schema/akka
`<code format="xml">`_
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:akka="http://akka.io/schema/akka"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://akka.io/schema/akka
http://akka.io/akka-1.0.xsd">
<!-- ... -->
</beans>
`<code>`_

View file

@ -219,18 +219,16 @@ Examples
with SmallestMailboxSelector
with BasicNoBackoffFilter
{
def factory = actorOf(new Actor {def receive = {case n:Int =>
Thread.sleep(n)
counter.incrementAndGet
latch.countDown()}})
def receive = _route
def lowerBound = 2
def upperBound = 4
def rampupRate = 0.1
def partialFill = true
def selectionCount = 1
def instance = factory
def receive = _route
def instance = actorOf(new Actor {def receive = {case n:Int =>
Thread.sleep(n)
counter.incrementAndGet
latch.countDown()}})
}
.. code-block:: scala
@ -243,11 +241,7 @@ Examples
with RunningMeanBackoff
with BasicRampup
{
def factory = actorOf(new Actor {def receive = {case n:Int =>
Thread.sleep(n)
latch.countDown()}})
def receive = _route
def lowerBound = 1
def upperBound = 5
def pressureThreshold = 1
@ -256,8 +250,9 @@ Examples
def rampupRate = 0.1
def backoffRate = 0.50
def backoffThreshold = 0.50
def instance = factory
def receive = _route
def instance = actorOf(new Actor {def receive = {case n:Int =>
Thread.sleep(n)
latch.countDown()}})
}
Taken from the unit test `spec <https://github.com/jboner/akka/blob/master/akka-actor/src/test/scala/akka/routing/RoutingSpec.scala>`_.

View file

@ -1,16 +0,0 @@
Scheduler
=========
Module stability: **SOLID**
Akka has a little scheduler written using actors. Can be convenient if you want to schedule some periodic task for maintenance or similar.
It allows you to register a message that you want to be sent to a specific actor at a periodic interval. Here is an example:
`<code format="scala">`_
//Sends messageToBeSent to receiverActor after initialDelayBeforeSending and then after each delayBetweenMessages
Scheduler.schedule(receiverActor, messageToBeSent, initialDelayBeforeSending, delayBetweenMessages, timeUnit)
//Sends messageToBeSent to receiverActor after delayUntilSend
Scheduler.scheduleOnce(receiverActor, messageToBeSent, delayUntilSend, timeUnit)
`<code>`_

View file

@ -1,22 +0,0 @@
Team
=====
|| **Name** || **Role** || **Email** ||
|| Jonas Bonér || Founder, Despot, Committer || jonas AT jonasboner DOT com ||
|| Viktor Klang || Bad cop, Committer || viktor DOT klang AT gmail DOT com ||
|| Debasish Ghosh || Committer || dghosh AT acm DOT org ||
|| Ross McDonald || Alumni || rossajmcd AT gmail DOT com ||
|| Eckhart Hertzler || Alumni || ||
|| Mikael Högqvist || Alumni || ||
|| Tim Perrett || Alumni || ||
|| Jeanfrancois Arcand || Alumni || jfarcand AT apache DOT org ||
|| Martin Krasser || Committer || krasserm AT googlemail DOT com ||
|| Jan Van Besien || Alumni || ||
|| Michael Kober || Committer || ||
|| Peter Vlugter || Committer || ||
|| Peter Veentjer || Committer || ||
|| Irmo Manie || Committer || ||
|| Heiko Seeberger || Committer || ||
|| Hiram Chirino || Committer || ||
|| Scott Clasen || Committer || ||
|| Roland Kuhn || Committer || ||

View file

@ -1,99 +0,0 @@
Web Framework Integrations
==========================
Play Framework
==============
Home page: `<http://www.playframework.org/>`_
Akka Play plugin: `<https://github.com/dwhitney/akka>`_
Read more here: `<http://www.playframework.org/modules/akka>`_
Lift Web Framework
==================
Home page: `<http://liftweb.net>`_
In order to use Akka with Lift you basically just have to do one thing, add the 'AkkaServlet' to your 'web.xml'.
web.xml
-------
.. code-block:: xml
<web-app>
<!-- Akka specific stuff -->
<servlet>
<servlet-name>AkkaServlet</servlet-name>
<servlet-class>akka.comet.AkkaServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>AkkaServlet</servlet-name>
<url-pattern>/*</url-pattern>
</servlet-mapping>
<!-- Lift specific stuff -->
<filter>
<filter-name>LiftFilter</filter-name>
<display-name>Lift Filter</display-name>
<description>The Filter that intercepts lift calls</description>
<filter-class>net.liftweb.http.LiftFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>LiftFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
</web-app>
Boot class
----------
Lift bootstrap happens in the Lift 'Boot' class. Here is a good place to add Akka specific initialization. For example add declarative supervisor configuration to wire up the initial Actors.
Here is a full example taken from the Akka sample code, found here `<http://github.com/jboner/akka/tree/master/akka-samples/akka-sample-lift/>`_.
If a request is processed by Liftweb filter, Akka will not process the request. To disable processing of a request by the Lift filter :
* append partial function to LiftRules.liftRequest and return *false* value to disable processing of matching request
* use LiftRules.passNotFoundToChain to chain the request to the Akka filter
Example of Boot class source code :
`<code format="scala">`_
class Boot {
def boot {
// where to search snippet
LiftRules.addToPackages("sample.lift")
LiftRules.httpAuthProtectedResource.prepend {
case (ParsePath("liftpage" :: Nil, _, _, _)) => Full(AuthRole("admin"))
}
LiftRules.authentication = HttpBasicAuthentication("lift") {
case ("someuser", "1234", req) => {
Log.info("You are now authenticated !")
userRoles(AuthRole("admin"))
true
}
}
LiftRules.liftRequest.append {
case Req("liftcount" :: _, _, _) => false
case Req("persistentliftcount" :: _, _, _) => false
}
LiftRules.passNotFoundToChain = true
// Akka supervisor configuration wiring up initial Actor services
val supervisor = Supervisor(
SupervisorConfig(
RestartStrategy(OneForOne, 3, 100, List(classOf[Exception])),
Supervise(
actorOf[SimpleService],
LifeCycle(Permanent)) ::
Supervise(
actorOf[PersistentSimpleService],
LifeCycle(Permanent)) ::
Nil))
// Build SiteMap
// val entries = Menu(Loc("Home", List("index"), "Home")) :: Nil
// LiftRules.setSiteMap(SiteMap(entries:_*))
}
}
`<code>`_

View file

@ -1,5 +1,9 @@
Actors
======
Actors (Scala)
==============
.. sidebar:: Contents
.. contents:: :local:
Module stability: **SOLID**
@ -26,6 +30,9 @@ Here is an example:
.. code-block:: scala
import akka.actor.Actor
import akka.event.EventHandler
class MyActor extends Actor {
def receive = {
case "test" => EventHandler.info(this, "received test")
@ -382,7 +389,7 @@ When you start the ``Actor`` then it will automatically call the ``def preStart`
.. code-block:: scala
override def preStart = {
override def preStart() = {
... // initialization code
}
@ -399,7 +406,7 @@ When stop is called then a call to the ``def postStop`` callback method will tak
.. code-block:: scala
override def postStop = {
override def postStop() = {
... // clean up resources
}

View file

@ -1,6 +1,10 @@
Agents (Scala)
==============
.. sidebar:: Contents
.. contents:: :local:
Module stability: **SOLID**
Agents in Akka were inspired by `agents in Clojure <http://clojure.org/agents>`_.
@ -88,6 +92,29 @@ Transactional Agents
If an Agent is used within an enclosing transaction, then it will participate in that transaction. If you send to an Agent within a transaction then the dispatch to the Agent will be held until that transaction commits, and discarded if the transaction is aborted.
.. code-block:: scala
import akka.agent.Agent
import akka.stm._
def transfer(from: Agent[Int], to: Agent[Int], amount: Int): Boolean = {
atomic {
if (from.get < amount) false
else {
from send (_ - amount)
to send (_ + amount)
true
}
}
}
val from = Agent(100)
val to = Agent(20)
val ok = transfer(from, to, 50)
from() // -> 50
to() // -> 70
Monadic usage
-------------

View file

@ -1,6 +1,10 @@
Dispatchers (Scala)
===================
.. sidebar:: Contents
.. contents:: :local:
Module stability: **SOLID**
The Dispatcher is an important piece that allows you to configure the right semantics and parameters for optimal performance, throughput and scalability. Different Actors have different needs.
@ -124,7 +128,7 @@ If you don't define a the 'throughput' option in the configuration file then the
Browse the `ScalaDoc <scaladoc>`_ or look at the code for all the options available.
Priority event-based
^^^^^^^^^^^
^^^^^^^^^^^^^^^^^^^^
Sometimes it's useful to be able to specify priority order of messages, that is done by using PriorityExecutorBasedEventDrivenDispatcher and supply
a java.util.Comparator[MessageInvocation] or use a akka.dispatch.PriorityGenerator (recommended):
@ -231,11 +235,13 @@ For the 'ExecutorBasedEventDrivenDispatcher' and the 'ExecutorBasedWorkStealingD
For the 'ThreadBasedDispatcher', it is non-shareable between actors, and associates a dedicated Thread with the actor.
Making it bounded (by specifying a capacity) is optional, but if you do, you need to provide a pushTimeout (default is 10 seconds). When trying to send a message to the Actor it will throw a MessageQueueAppendFailedException("BlockingMessageTransferQueue transfer timed out") if the message cannot be added to the mailbox within the time specified by the pushTimeout.
`<code format="scala">`_
class MyActor extends Actor {
import akka.util.duration._
self.dispatcher = Dispatchers.newThreadBasedDispatcher(self, mailboxCapacity = 100,
pushTimeOut = 10 seconds)
...
}
`<code>`_
.. code-block:: scala
class MyActor extends Actor {
import akka.util.duration._
self.dispatcher = Dispatchers.newThreadBasedDispatcher(self, mailboxCapacity = 100,
pushTimeOut = 10 seconds)
...
}

View file

@ -49,13 +49,14 @@ Now lets create an object representing the FSM and defining the behavior.
import akka.actor.{Actor, FSM}
import akka.event.EventHandler
import FSM._
import akka.util.duration._
case object Move
class ABC extends Actor with FSM[ExampleState, Unit] {
import FSM._
startWith(A, Unit)
when(A) {

View file

@ -5,5 +5,14 @@ Scala API
:maxdepth: 2
actors
typed-actors
actor-registry
agents
stm
transactors
remote-actors
serialization
dispatchers
fsm
testing
tutorial-chat-server

View file

@ -1,13 +1,17 @@
Remote Actors (Scala)
=====================
.. sidebar:: Contents
.. contents:: :local:
Module stability: **SOLID**
Akka supports starting Actors and Typed Actors on remote nodes using a very efficient and scalable NIO implementation built upon `JBoss Netty <http://jboss.org/netty>`_ and `Google Protocol Buffers <http://code.google.com/p/protobuf/>`_ .
Akka supports starting and interacting with Actors and Typed Actors on remote nodes using a very efficient and scalable NIO implementation built upon `JBoss Netty <http://jboss.org/netty>`_ and `Google Protocol Buffers <http://code.google.com/p/protobuf/>`_ .
The usage is completely transparent both in regards to sending messages and error handling and propagation as well as supervision, linking and restarts. You can send references to other Actors as part of the message.
The usage is completely transparent with local actors, both in regards to sending messages and error handling and propagation as well as supervision, linking and restarts. You can send references to other Actors as part of the message.
You can find a runnable sample `here <http://github.com/jboner/akka/tree/master/akka-samples/akka-sample-remote/>`_.
You can find a runnable sample `here <http://github.com/jboner/akka/tree/master/akka-samples/akka-sample-remote/>`__.
Starting up the remote service
------------------------------
@ -64,7 +68,7 @@ If you invoke 'shutdown' on the server then the connection will be closed.
import akka.actor.Actor._
remote.shutdown
remote.shutdown()
Connecting and shutting down a client explicitly
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -74,6 +78,7 @@ Normally you should not have to start and stop the client connection explicitly
.. code-block:: scala
import akka.actor.Actor._
import java.net.InetSocketAddress
remote.shutdownClientConnection(new InetSocketAddress("localhost", 6666)) //Returns true if successful, false otherwise
remote.restartClientConnection(new InetSocketAddress("localhost", 6666)) //Returns true if successful, false otherwise
@ -143,12 +148,6 @@ The default behavior is that the remote client will maintain a transaction log o
If you choose a capacity higher than 0, then a bounded queue will be used and if the limit of the queue is reached then a 'RemoteClientMessageBufferException' will be thrown.
You can also get an Array with all the messages that the remote client has failed to send. Since the remote client events passes you an instance of the RemoteClient you have an easy way to act upon failure and do something with these messages (while waiting for them to be retried).
.. code-block:: scala
val pending: Array[Any] = Actor.remote.pendingMessages
Running Remote Server in untrusted mode
---------------------------------------
@ -255,24 +254,16 @@ You can also generate the secure cookie by using the 'Crypt' object and its 'gen
The secure cookie is a cryptographically secure randomly generated byte array turned into a SHA-1 hash.
Remote Actors
-------------
Akka has two types of remote actors:
* Client-initiated and managed. Here it is the client that creates the remote actor and "moves it" to the server.
* Server-initiated and managed. Here it is the server that creates the remote actor and the client can ask for a handle to this actor.
They are good for different use-cases. The client-initiated are great when you want to monitor an actor on another node since it allows you to link to it and supervise it using the regular supervision semantics. They also make RPC completely transparent. The server-initiated, on the other hand, are great when you have a service running on the server that you want clients to connect to, and you want full control over the actor on the server side for security reasons etc.
Client-managed Remote Actors
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
----------------------------
DEPRECATED AS OF 1.1
When you define an actors as being remote it is instantiated as on the remote host and your local actor becomes a proxy, it works as a handle to the remote actor. The real execution is always happening on the remote node.
The client creates the remote actor and "moves it" to the server.
Actors can be made remote by calling remote().actorOf[MyActor](host, port)
When you define an actor as being remote it is instantiated as on the remote host and your local actor becomes a proxy, it works as a handle to the remote actor. The real execution is always happening on the remote node.
Actors can be made remote by calling remote.actorOf[MyActor](host, port)
Here is an example:
@ -280,29 +271,30 @@ Here is an example:
import akka.actor.Actor
class MyActor extends RemoteActor() {
class MyActor extends Actor {
def receive = {
case "hello" => self.reply("world")
}
}
val remote = Actor.remote().actorOf[MyActor]("192.68.23.769", 2552)
val remoteActor = Actor.remote.actorOf[MyActor]("192.68.23.769", 2552)
An Actor can also start remote child Actors through one of the 'spawn/link' methods. These will start, link and make the Actor remote atomically.
.. code-block:: scala
...
spawnRemote[MyActor](hostname, port)
spawnLinkRemote[MyActor](hostname, port)
self.spawnRemote[MyActor](hostname, port, timeout)
self.spawnLinkRemote[MyActor](hostname, port, timeout)
...
Server-managed Remote Actors
----------------------------
Here it is the server that creates the remote actor and the client can ask for a handle to this actor.
Server side setup
^^^^^^^^^^^^^^^^^
The API for server managed remote actors is really simple. 2 methods only:
.. code-block:: scala
@ -332,7 +324,7 @@ Session bound server side setup
Session bound server managed remote actors work by creating and starting a new actor for every client that connects. Actors are stopped automatically when the client disconnects. The client side is the same as regular server managed remote actors. Use the function registerPerSession instead of register.
Session bound actors are useful if you need to keep state per session, e.g. username.
They are also useful if you need to perform some cleanup when a client disconnects by overriding the postStop method as described `here <actors-scala#Stopping actors>`_
They are also useful if you need to perform some cleanup when a client disconnects by overriding the postStop method as described `here <actors-scala#Stopping actors>`__
.. code-block:: scala
@ -358,10 +350,10 @@ There are many variations on the 'remote#actorFor' method. Here are some of them
.. code-block:: scala
... = actorFor(className, hostname, port)
... = actorFor(className, timeout, hostname, port)
... = actorFor(uuid, className, hostname, port)
... = actorFor(uuid, className, timeout, hostname, port)
... = remote.actorFor(className, hostname, port)
... = remote.actorFor(className, timeout, hostname, port)
... = remote.actorFor(uuid, className, hostname, port)
... = remote.actorFor(uuid, className, timeout, hostname, port)
... // etc
All of these also have variations where you can pass in an explicit 'ClassLoader' which can be used when deserializing messages sent from the remote actor.
@ -371,11 +363,16 @@ Running sample
Here is a complete running sample (also available `here <http://github.com/jboner/akka/blob/master/akka-core/src/test/scala/ServerInitiatedRemoteActorSample.scala>`_):
Paste in the code below into two sbt concole shells. Then run:
- ServerInitiatedRemoteActorServer.run() in one shell
- ServerInitiatedRemoteActorClient.run() in the other shell
.. code-block:: scala
import akka.actor.Actor
import akka.util.Logging
import Actor._
import akka.event.EventHandler
class HelloWorldActor extends Actor {
def receive = {
@ -385,27 +382,27 @@ Here is a complete running sample (also available `here <http://github.com/jbone
object ServerInitiatedRemoteActorServer {
def run = {
def run() {
remote.start("localhost", 2552)
remote.register("hello-service", actorOf[HelloWorldActor])
}
def main(args: Array[String]) = run
def main(args: Array[String]) { run() }
}
object ServerInitiatedRemoteActorClient extends Logging {
object ServerInitiatedRemoteActorClient {
def run = {
def run() {
val actor = remote.actorFor("hello-service", "localhost", 2552)
val result = actor !! "Hello"
log.info("Result from Remote Actor: %s", result)
EventHandler.info("Result from Remote Actor: %s", result)
}
def main(args: Array[String]) = run
def main(args: Array[String]) { run() }
}
Automatic remote 'sender' reference management
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
----------------------------------------------
The sender of a remote message will be reachable with a reply through the remote server on the node that the actor is residing, automatically.
Please note that firewalled clients won't work right now. [2011-01-05]
@ -419,10 +416,10 @@ Here is an example of overriding the 'id' field:
.. code-block:: scala
import akka.util.UUID
import akka.actor.newUuid
class MyActor extends Actor {
self.id = UUID.newUuid.toString
self.id = newUuid.toString
def receive = {
case "hello" => self.reply("world")
}
@ -430,11 +427,9 @@ Here is an example of overriding the 'id' field:
val actor = remote.actorOf[MyActor]("192.68.23.769", 2552)
Remote Typed Actors
-------------------
Client-managed Remote Actors
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Client-managed Remote Typed Actors
----------------------------------
DEPRECATED AS OF 1.1
@ -458,13 +453,13 @@ You can also define an Typed Actor to be remote programmatically when creating i
... // use pojo as usual
Server-managed Remote Actors
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Server-managed Remote Typed Actors
----------------------------------
WARNING: Remote TypedActors do not work with overloaded methods on your TypedActor, refrain from using overloading.
Server side setup
*****************
^^^^^^^^^^^^^^^^^
The API for server managed remote typed actors is nearly the same as for untyped actor
@ -507,20 +502,20 @@ They are also useful if you need to perform some cleanup when a client disconnec
Note that the second argument in registerTypedPerSessionActor is an implicit function. It will be called to create an actor every time a session is established.
Client side usage
*****************
^^^^^^^^^^^^^^^^^
.. code-block:: scala
val actor = remote.typedActorFor(classOf[RegistrationService], "user-service", 5000L, "localhost", 2552)
actor.registerUser(…)
There are variations on the 'RemoteClient#typedActorFor' method. Here are some of them:
There are variations on the 'remote#typedActorFor' method. Here are some of them:
.. code-block:: scala
... = typedActorFor(interfaceClazz, serviceIdOrClassName, hostname, port)
... = typedActorFor(interfaceClazz, serviceIdOrClassName, timeout, hostname, port)
... = typedActorFor(interfaceClazz, serviceIdOrClassName, timeout, hostname, port, classLoader)
... = remote.typedActorFor(interfaceClazz, serviceIdOrClassName, hostname, port)
... = remote.typedActorFor(interfaceClazz, serviceIdOrClassName, timeout, hostname, port)
... = remote.typedActorFor(interfaceClazz, serviceIdOrClassName, timeout, hostname, port, classLoader)
Data Compression Configuration
------------------------------
@ -583,15 +578,19 @@ So a simple listener actor can look like this:
.. code-block:: scala
import akka.actor.Actor
import akka.actor.Actor._
import akka.remoteinterface._
val listener = actorOf(new Actor {
def receive = {
case RemoteClientError(cause, client, address) => ... // act upon error
case RemoteClientDisconnected(client, address) => ... // act upon disconnection
case RemoteClientConnected(client, address) => ... // act upon connection
case RemoteClientStarted(client, address) => ... // act upon client shutdown
case RemoteClientShutdown(client, address) => ... // act upon client shutdown
case RemoteClientWriteFailed(request, cause, client, address) => ... // act upon write failure
case _ => //ignore other
case RemoteClientError(cause, client, address) => //... act upon error
case RemoteClientDisconnected(client, address) => //... act upon disconnection
case RemoteClientConnected(client, address) => //... act upon connection
case RemoteClientStarted(client, address) => //... act upon client shutdown
case RemoteClientShutdown(client, address) => //... act upon client shutdown
case RemoteClientWriteFailed(request, cause, client, address) => //... act upon write failure
case _ => // ignore other
}
}).start()
@ -637,15 +636,19 @@ So a simple listener actor can look like this:
.. code-block:: scala
import akka.actor.Actor
import akka.actor.Actor._
import akka.remoteinterface._
val listener = actorOf(new Actor {
def receive = {
case RemoteServerStarted(server) => ... // act upon server start
case RemoteServerShutdown(server) => ... // act upon server shutdown
case RemoteServerError(cause, server) => ... // act upon server error
case RemoteServerClientConnected(server, clientAddress) => ... // act upon client connection
case RemoteServerClientDisconnected(server, clientAddress) => ... // act upon client disconnection
case RemoteServerClientClosed(server, clientAddress) => ... // act upon client connection close
case RemoteServerWriteFailed(request, cause, server, clientAddress) => ... // act upon server write failure
case RemoteServerStarted(server) => //... act upon server start
case RemoteServerShutdown(server) => //... act upon server shutdown
case RemoteServerError(cause, server) => //... act upon server error
case RemoteServerClientConnected(server, clientAddress) => //... act upon client connection
case RemoteServerClientDisconnected(server, clientAddress) => //... act upon client disconnection
case RemoteServerClientClosed(server, clientAddress) => //... act upon client connection close
case RemoteServerWriteFailed(request, cause, server, clientAddress) => //... act upon server write failure
}
}).start()
@ -662,7 +665,7 @@ Message Serialization
All messages that are sent to remote actors needs to be serialized to binary format to be able to travel over the wire to the remote node. This is done by letting your messages extend one of the traits in the 'akka.serialization.Serializable' object. If the messages don't implement any specific serialization trait then the runtime will try to use standard Java serialization.
Here are some examples, but full documentation can be found in the `Serialization section <serialization>`_.
Here are some examples, but full documentation can be found in the :ref:`serialization-scala`.
Scala JSON
^^^^^^^^^^
@ -676,7 +679,7 @@ Protobuf
Protobuf message specification needs to be compiled with 'protoc' compiler.
.. code-block:: scala
::
message ProtobufPOJO {
required uint64 id = 1;
@ -697,26 +700,27 @@ Using the generated message builder to send the message to a remote actor:
SBinary
^^^^^^^
`<code format="scala">`_
case class User(firstNameLastName: Tuple2[String, String], email: String, age: Int) extends Serializable.SBinary[User] {
import sbinary.DefaultProtocol._
.. code-block:: scala
def this() = this(null, null, 0)
case class User(firstNameLastName: Tuple2[String, String], email: String, age: Int) extends Serializable.SBinary[User] {
import sbinary.DefaultProtocol._
implicit object UserFormat extends Format[User] {
def reads(in : Input) = User(
read[Tuple2[String, String]](in),
read[String](in),
read[Int](in))
def writes(out: Output, value: User) = {
write[Tuple2[String, String]](out, value. firstNameLastName)
write[String](out, value.email)
write[Int](out, value.age)
def this() = this(null, null, 0)
implicit object UserFormat extends Format[User] {
def reads(in : Input) = User(
read[Tuple2[String, String]](in),
read[String](in),
read[Int](in))
def writes(out: Output, value: User) = {
write[Tuple2[String, String]](out, value. firstNameLastName)
write[String](out, value.email)
write[Int](out, value.age)
}
}
def fromBytes(bytes: Array[Byte]) = fromByteArray[User](bytes)
def toBytes: Array[Byte] = toByteArray(this)
}
def fromBytes(bytes: Array[Byte]) = fromByteArray[User](bytes)
def toBytes: Array[Byte] = toByteArray(this)
}
`<code>`_

View file

@ -1,10 +1,16 @@
.. _serialization-scala:
Serialization (Scala)
=====================
.. sidebar:: Contents
.. contents:: :local:
Module stability: **SOLID**
Serialization of ActorRef
=========================
-------------------------
An Actor can be serialized in two different ways:
@ -13,7 +19,7 @@ An Actor can be serialized in two different ways:
Both of these can be sent as messages over the network and/or store them to disk, in a persistent storage backend etc.
Actor serialization in Akka is implemented through a type class 'Format[T <: Actor]' which publishes the 'fromBinary' and 'toBinary' methods for serialization. Here's the complete definition of the type class:
Actor serialization in Akka is implemented through a type class ``Format[T <: Actor]`` which publishes the ``fromBinary`` and ``toBinary`` methods for serialization. Here's the complete definition of the type class:
.. code-block:: scala
@ -31,15 +37,14 @@ Actor serialization in Akka is implemented through a type class 'Format[T <: Act
// client needs to implement Format[] for the respective actor
trait Format[T <: Actor] extends FromBinary[T] with ToBinary[T]
**Deep serialization of an Actor and ActorRef**
-----------------------------------------------
Deep serialization of an Actor and ActorRef
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
You can serialize the whole actor deeply, e.g. both the 'ActorRef' and then instance of its 'Actor'. This can be useful if you want to move an actor from one node to another, or if you want to store away an actor, with its state, into a database.
You can serialize the whole actor deeply, e.g. both the ``ActorRef`` and then instance of its ``Actor``. This can be useful if you want to move an actor from one node to another, or if you want to store away an actor, with its state, into a database.
Here is an example of how to serialize an Actor.
Step 1: Define the actor
^^^^^^^^^^^^^^^^^^^^^^^^
.. code-block:: scala
@ -53,11 +58,15 @@ Step 1: Define the actor
}
}
Step 2: Implement the type class for the actor
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Step 2: Implement the type class for the actor. ProtobufProtocol.Counter is something you need to define yourself, as
explained in the Protobuf section.
.. code-block:: scala
import akka.serialization.{Serializer, Format}
import akka.actor.Actor
import akka.actor.Actor._
object BinaryFormatMyActor {
implicit object MyActorFormat extends Format[MyActor] {
def fromBinary(bytes: Array[Byte], act: MyActor) = {
@ -66,13 +75,11 @@ Step 2: Implement the type class for the actor
act
}
def toBinary(ac: MyActor) =
ProtobufProtocol.Counter.newBuilder.setCount(ac.count).build.toByteArray
}
ProtobufProtocol.Counter.newBuilder.setCount(ac.count).build.toByteArray
}
}
Step 3: Import the type class module definition and serialize / de-serialize
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
.. code-block:: scala
@ -90,7 +97,8 @@ Step 3: Import the type class module definition and serialize / de-serialize
(actor2 !! "hello").getOrElse("_") should equal("world 3")
}
**Helper Type Class for Stateless Actors**
Helper Type Class for Stateless Actors
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
If your actor is stateless, then you can use the helper trait that Akka provides to serialize / de-serialize. Here's the definition:
@ -138,9 +146,10 @@ and use it for serialization:
(actor2 !! "hello").getOrElse("_") should equal("world")
}
**Helper Type Class for actors with external serializer**
Helper Type Class for actors with external serializer
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Use the trait 'SerializerBasedActorFormat' for specifying serializers.
Use the trait ``SerializerBasedActorFormat`` for specifying serializers.
.. code-block:: scala
@ -154,7 +163,7 @@ For a Java serializable actor:
.. code-block:: scala
@serializable class MyJavaSerializableActor extends Actor {
class MyJavaSerializableActor extends Actor with scala.Serializable {
var count = 0
def receive = {
@ -168,6 +177,8 @@ Create a module for the type class ..
.. code-block:: scala
import akka.serialization.{SerializerBasedActorFormat, Serializer}
object BinaryFormatMyJavaSerializableActor {
implicit object MyJavaSerializableActorFormat extends SerializerBasedActorFormat[MyJavaSerializableActor] {
val serializer = Serializer.Java
@ -179,6 +190,7 @@ and serialize / de-serialize ..
.. code-block:: scala
it("should be able to serialize and de-serialize a stateful actor with a given serializer") {
import akka.actor.Actor._
import akka.serialization.ActorSerialization._
import BinaryFormatMyJavaSerializableActor._
@ -192,14 +204,14 @@ and serialize / de-serialize ..
(actor2 !! "hello").getOrElse("_") should equal("world 3")
}
**Serialization of a RemoteActorRef**
-------------------------------------
Serialization of a RemoteActorRef
---------------------------------
You can serialize an 'ActorRef' to an immutable, network-aware Actor reference that can be freely shared across the network, a reference that "remembers" and stay mapped to its original Actor instance and host node, and will always work as expected.
You can serialize an ``ActorRef`` to an immutable, network-aware Actor reference that can be freely shared across the network, a reference that "remembers" and stay mapped to its original Actor instance and host node, and will always work as expected.
The 'RemoteActorRef' serialization is based upon Protobuf (Google Protocol Buffers) and you don't need to do anything to use it, it works on any 'ActorRef' (as long as the actor has **not** implemented one of the 'SerializableActor' traits, since then deep serialization will happen).
The ``RemoteActorRef`` serialization is based upon Protobuf (Google Protocol Buffers) and you don't need to do anything to use it, it works on any ``ActorRef``.
Currently Akka will **not** autodetect an 'ActorRef' as part of your message and serialize it for you automatically, so you have to do that manually or as part of your custom serialization mechanisms.
Currently Akka will **not** autodetect an ``ActorRef`` as part of your message and serialize it for you automatically, so you have to do that manually or as part of your custom serialization mechanisms.
Here is an example of how to serialize an Actor.
@ -209,34 +221,34 @@ Here is an example of how to serialize an Actor.
val bytes = toBinary(actor1)
To deserialize the 'ActorRef' to a 'RemoteActorRef' you need to use the 'fromBinaryToRemoteActorRef(bytes: Array[Byte])' method on the 'ActorRef' companion object:
To deserialize the ``ActorRef`` to a ``RemoteActorRef`` you need to use the ``fromBinaryToRemoteActorRef(bytes: Array[Byte])`` method on the ``ActorRef`` companion object:
.. code-block:: scala
import RemoteActorSerialization._
import akka.serialization.RemoteActorSerialization._
val actor2 = fromBinaryToRemoteActorRef(bytes)
You can also pass in a class loader to load the 'ActorRef' class and dependencies from:
You can also pass in a class loader to load the ``ActorRef`` class and dependencies from:
.. code-block:: scala
import RemoteActorSerialization._
import akka.serialization.RemoteActorSerialization._
val actor2 = fromBinaryToRemoteActorRef(bytes, classLoader)
Deep serialization of a TypedActor
----------------------------------
Serialization of typed actors works almost the same way as untyped actors. You can serialize the whole actor deeply, e.g. both the 'proxied ActorRef' and the instance of its 'TypedActor'.
Serialization of typed actors works almost the same way as untyped actors. You can serialize the whole actor deeply, e.g. both the 'proxied ActorRef' and the instance of its ``TypedActor``.
Here is the example from above implemented as a TypedActor.
^
Step 1: Define the actor
^^^^^^^^^^^^^^^^^^^^^^^^
.. code-block:: scala
import akka.actor.TypedActor
trait MyTypedActor {
def requestReply(s: String) : String
def oneWay() : Unit
@ -249,13 +261,18 @@ Step 1: Define the actor
count = count + 1
"world " + count
}
override def oneWay() {
count = count + 1
}
}
Step 2: Implement the type class for the actor
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
.. code-block:: scala
import akka.serialization.{Serializer, Format}
class MyTypedActorFormat extends Format[MyTypedActorImpl] {
def fromBinary(bytes: Array[Byte], act: MyTypedActorImpl) = {
val p = Serializer.Protobuf.fromBinary(bytes, Some(classOf[ProtobufProtocol.Counter])).asInstanceOf[ProtobufProtocol.Counter]
@ -266,10 +283,11 @@ Step 2: Implement the type class for the actor
}
Step 3: Import the type class module definition and serialize / de-serialize
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
.. code-block:: scala
import akka.serialization.TypedActorSerialization._
val typedActor1 = TypedActor.newInstance(classOf[MyTypedActor], classOf[MyTypedActorImpl], 1000)
val f = new MyTypedActorFormat
@ -278,23 +296,23 @@ Step 3: Import the type class module definition and serialize / de-serialize
val typedActor2: MyTypedActor = fromBinaryJ(bytes, f) //type hint needed
typedActor2.requestReply("hello")
-
Serialization of a remote typed ActorRef
----------------------------------------
To deserialize the TypedActor to a 'RemoteTypedActorRef' (an aspectwerkz proxy to a RemoteActorRef) you need to use the 'fromBinaryToRemoteTypedActorRef(bytes: Array[Byte])' method on 'RemoteTypedActorSerialization' object:
To deserialize the TypedActor to a ``RemoteTypedActorRef`` (an aspectwerkz proxy to a RemoteActorRef) you need to use the ``fromBinaryToRemoteTypedActorRef(bytes: Array[Byte])`` method on ``RemoteTypedActorSerialization`` object:
.. code-block:: scala
import RemoteTypedActorSerialization._
import akka.serialization.RemoteTypedActorSerialization._
val typedActor = fromBinaryToRemoteTypedActorRef(bytes)
// you can also pass in a class loader
val typedActor2 = fromBinaryToRemoteTypedActorRef(bytes, classLoader)
Compression
===========
-----------
Akka has a helper class for doing compression of binary data. This can be useful for example when storing data in one of the backing storages. It currently supports LZF which is a very fast compression algorithm suited for runtime dynamic compression.
@ -309,24 +327,27 @@ Here is an example of how it can be used:
val uncompressBytes = Compression.LZF.uncompress(compressBytes)
Using the Serializable trait and Serializer class for custom serialization
==========================================================================
--------------------------------------------------------------------------
If you are sending messages to a remote Actor and these messages implement one of the predefined interfaces/traits in the 'akka.serialization.Serializable.*' object, then Akka will transparently detect which serialization format it should use as wire protocol and will automatically serialize and deserialize the message according to this protocol.
If you are sending messages to a remote Actor and these messages implement one of the predefined interfaces/traits in the ``akka.serialization.Serializable.*`` object, then Akka will transparently detect which serialization format it should use as wire protocol and will automatically serialize and deserialize the message according to this protocol.
Each serialization interface/trait in
* akka.serialization.Serializable.*
> has a matching serializer in
* akka.serialization.Serializer.*
- akka.serialization.Serializable.*
has a matching serializer in
- akka.serialization.Serializer.*
Note however that if you are using one of the Serializable interfaces then you dont have to do anything else in regard to sending remote messages.
The ones currently supported are (besides the default which is regular Java serialization):
* ScalaJSON (Scala only)
* JavaJSON (Java but some Scala structures)
* SBinary (Scala only)
* Protobuf (Scala and Java)
Apart from the above, Akka also supports Scala object serialization through `SJSON <http://github.com/debasishg/sjson/tree/master>`_ that implements APIs similar to 'akka.serialization.Serializer.*'. See the section on SJSON below for details.
- ScalaJSON (Scala only)
- JavaJSON (Java but some Scala structures)
- Protobuf (Scala and Java)
Apart from the above, Akka also supports Scala object serialization through `SJSON <http://github.com/debasishg/sjson/tree/master>`_ that implements APIs similar to ``akka.serialization.Serializer.*``. See the section on SJSON below for details.
Protobuf
--------
@ -372,15 +393,16 @@ The remote Actor can then receive the Protobuf message typed as-is:
JSON: Scala
-----------
Use the akka.serialization.Serialization.ScalaJSON base class with its toJSON method. Akkas Scala JSON is based upon the SJSON library.
Use the ``akka.serialization.Serializable.ScalaJSON`` base class with its toJSON method. Akkas Scala JSON is based upon the SJSON library.
For your POJOs to be able to serialize themselves you have to extend the ScalaJSON[] trait as follows. JSON serialization is based on a type class protocol which you need to define for your own abstraction. The instance of the type class is defined as an implicit object which is used for serialization and de-serialization. You also need to implement the methods in terms of the APIs which sjson publishes.
.. code-block:: scala
import akka.serialization.Serializer
import akka.serialization._
import akka.serialization.Serializable.ScalaJSON
import scala.reflect.BeanInfo
import akka.serialization.JsonSerialization._
import akka.serialization.DefaultProtocol._
case class MyMessage(val id: String, val value: Tuple2[String, Int]) extends ScalaJSON[MyMessage] {
// type class instance
@ -422,7 +444,7 @@ Here are the steps that you need to follow:
.. code-block:: scala
import DefaultProtocol._
import akka.serialization.DefaultProtocol._
implicit val MyMessageFormat: sjson.json.Format[MyMessage] =
asProduct2("id", "value")(MyMessage)(MyMessage.unapply(_).get)
@ -431,6 +453,7 @@ Here are the steps that you need to follow:
.. code-block:: scala
import akka.serialization.Serializer.ScalaJSON
import akka.serialization.JsonSerialization._
val o = MyMessage("dg", ("akka", 100))
fromjson[MyMessage](tojson(o)) should equal(o)
@ -475,14 +498,14 @@ So if you see something like that:
it means, that you haven't got a @BeanInfo annotation on your class.
You may also see this exception when trying to serialize a case class with out an attribute like this:
You may also see this exception when trying to serialize a case class without any attributes, like this:
.. code-block:: scala
@BeanInfo case class Empty() // cannot be serialized
SJSON: Scala
-------------
SJSON: Scala
------------
SJSON supports serialization of Scala objects into JSON. It implements support for built in Scala structures like List, Map or String as well as custom objects. SJSON is available as an Apache 2 licensed project on Github `here <http://github.com/debasishg/sjson/tree/master>`_.
@ -535,7 +558,7 @@ What you get back from is a JsValue, an abstraction of the JSON object model. Fo
Serialization of Embedded Objects
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
SJSON supports serialization of Scala objects that have other embedded objects. Suppose you have the following Scala classes .. Here Contact has an embedded Address Map ..
SJSON supports serialization of Scala objects that have other embedded objects. Suppose you have the following Scala classes .. Here Contact has an embedded Address Map ..
.. code-block:: scala
@ -593,7 +616,7 @@ With SJSON, I can do the following:
"Market Street" should equal(
(r ># { ('addresses ? obj) andThen ('residence ? obj) andThen ('street ? str) }))
^
Changing property names during serialization
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -619,7 +642,7 @@ When this will be serialized out, the property name will be changed.
JsString("ISBN") -> JsString("012-456372")
)
^
Serialization with ignore properties
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -653,7 +676,7 @@ The annotation @JSONProperty can be used to selectively ignore fields. When I se
Similarly, we can ignore properties of an object **only** if they are null and not ignore otherwise. Just specify the annotation @JSONProperty as @JSONProperty {val ignoreIfNull = true}.
^
Serialization with Type Hints for Generic Data Members
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -892,14 +915,18 @@ and the serialization in action in the REPL:
There are other nifty ways to implement case class serialization using sjson. For more details, have a look at the `wiki <http://wiki.github.com/debasishg/sjson/typeclass-based-json-serialization>`_ for sjson.
**<span class="caps" style="line-height: 1.4em; margin: 0px; padding: 0px;">JSON</span>: Java**
JSON: Java
----------
Use the akka.serialization.Serialization.JavaJSON base class with its toJSONmethod. Akkas Java JSON is based upon the Jackson library.
Use the ``akka.serialization.Serializable.JavaJSON`` base class with its toJSONmethod. Akkas Java JSON is based upon the Jackson library.
For your POJOs to be able to serialize themselves you have to extend the JavaJSON trait.
For your POJOs to be able to serialize themselves you have to extend the JavaJSON base class.
.. code-block:: java
import akka.serialization.Serializable.JavaJSON;
import akka.serialization.SerializerFactory;
class MyMessage extends JavaJSON {
private String name = null;
public MyMessage(String name) {
@ -924,55 +951,5 @@ Use the akka.serialization.SerializerFactory.getJavaJSON to do generic JSON seri
String json = factory.getJavaJSON().out(foo);
Foo fooCopy = factory.getJavaJSON().in(json, Foo.class);
-
SBinary: Scala
--------------
To serialize Scala structures you can use SBinary serializer. SBinary can serialize all primitives and most default Scala datastructures; such as List, Tuple, Map, Set, BigInt etc.
Here is an example of using the akka.serialization.Serializer.SBinary serializer to serialize standard Scala library objects.
.. code-block:: scala
import akka.serialization.Serializer
import sbinary.DefaultProtocol._ // you always need to import these implicits
val users = List(("user1", "passwd1"), ("user2", "passwd2"), ("user3", "passwd3"))
val bytes = Serializer.SBinary.out(users)
val usersCopy = Serializer.SBinary.in(bytes, Some(classOf[List[Tuple2[String,String]]]))
If you need to serialize your own user-defined objects then you have to do three things:
# Define an empty constructor
# Mix in the Serializable.SBinary[T] trait, and implement its methods:
## fromBytes(bytes: Array[Byte])[T]
## toBytes: Array[Byte]
# Create an implicit sbinary.Format[T] object for your class. Which means that you have to define its two methods:
## reads(in: Input): T; in which you read in all the fields in your object, using read[FieldType](in)and recreate it.
## writes(out: Output, value: T): Unit; in which you write out all the fields in your object, using write[FieldType](out, value.field).
Here is an example:
`<code format="scala">`_
case class User(val usernamePassword: Tuple2[String, String], val email: String, val age: Int)
extends Serializable.SBinary[User] {
import sbinary.DefaultProtocol._
import sbinary.Operations._
def this() = this(null, null, 0)
implicit object UserFormat extends Format[User] {
def reads(in : Input) = User(
read[Tuple2[String, String]](in),
read[String](in),
read[Int](in))
def writes(out: Output, value: User) = {
write[Tuple2[String, String]](out, value.usernamePassword)
write[String](out, value.email)
write[Int](out, value.age)
}
}
def fromBytes(bytes: Array[Byte]) = fromByteArray[User](bytes)
def toBytes: Array[Byte] = toByteArray(this)
}
`<code>`_

View file

@ -1,10 +1,14 @@
Software Transactional Memory (Scala)
=====================================
.. sidebar:: Contents
.. contents:: :local:
Module stability: **SOLID**
Overview of STM
===============
---------------
An `STM <http://en.wikipedia.org/wiki/Software_transactional_memory>`_ turns the Java heap into a transactional data set with begin/commit/rollback semantics. Very much like a regular database. It implements the first three letters in ACID; ACI:
* Atomic
@ -24,7 +28,7 @@ The STM is based on Transactional References (referred to as Refs). Refs are mem
Working with immutable collections can sometimes give bad performance due to extensive copying. Scala provides so-called persistent datastructures which makes working with immutable collections fast. They are immutable but with constant time access and modification. They use structural sharing and an insert or update does not ruin the old structure, hence “persistent”. Makes working with immutable composite types fast. The persistent datastructures currently consist of a Map and Vector.
Simple example
==============
--------------
Here is a simple example of an incremental counter using STM. This shows creating a ``Ref``, a transactional reference, and then modifying it within a transaction, which is delimited by ``atomic``.
@ -44,15 +48,14 @@ Here is a simple example of an incremental counter using STM. This shows creatin
counter
// -> 2
----
Ref
===
---
Refs (transactional references) are mutable references to values and through the STM allow the safe sharing of mutable data. Refs separate identity from value. To ensure safety the value stored in a Ref should be immutable (they can of course contain refs themselves). The value referenced by a Ref can only be accessed or swapped within a transaction. If a transaction is not available, the call will be executed in its own transaction (the call will be atomic). This is a different approach than the Clojure Refs, where a missing transaction results in an error.
Creating a Ref
--------------
^^^^^^^^^^^^^^
You can create a Ref with or without an initial value.
@ -67,7 +70,7 @@ You can create a Ref with or without an initial value.
val ref = Ref[Int]
Accessing the value of a Ref
----------------------------
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Use ``get`` to access the value of a Ref. Note that if no initial value has been given then the value is initially ``null``.
@ -97,7 +100,7 @@ If there is a chance that the value of a Ref is null then you can use ``opt``, w
}
Changing the value of a Ref
---------------------------
^^^^^^^^^^^^^^^^^^^^^^^^^^^
To set a new value for a Ref you can use ``set`` (or equivalently ``swap``), which sets the new value and returns the old value.
@ -138,7 +141,7 @@ You can also use ``alter`` which accepts a function that takes the old value and
// -> 6
Refs in for-comprehensions
--------------------------
^^^^^^^^^^^^^^^^^^^^^^^^^^
Ref is monadic and can be used in for-comprehensions.
@ -174,10 +177,9 @@ Ref is monadic and can be used in for-comprehensions.
}
// -> Ref[Int]
----
Transactions
============
------------
A transaction is delimited using ``atomic``.
@ -190,24 +192,24 @@ A transaction is delimited using ``atomic``.
All changes made to transactional objects are isolated from other changes, all make it or non make it (so failure atomicity) and are consistent. With the AkkaSTM you automatically have the Oracle version of the SERIALIZED isolation level, lower isolation is not possible. To make it fully serialized, set the writeskew property that checks if a writeskew problem is allowed to happen.
Retries
-------
^^^^^^^
A transaction is automatically retried when it runs into some read or write conflict, until the operation completes, an exception (throwable) is thrown or when there are too many retries. When a read or writeconflict is encountered, the transaction uses a bounded exponential backoff to prevent cause more contention and give other transactions some room to complete.
If you are using non transactional resources in an atomic block, there could be problems because a transaction can be retried. If you are using print statements or logging, it could be that they are called more than once. So you need to be prepared to deal with this. One of the possible solutions is to work with a deferred or compensating task that is executed after the transaction aborts or commits.
Unexpected retries
------------------
^^^^^^^^^^^^^^^^^^
It can happen for the first few executions that you get a few failures of execution that lead to unexpected retries, even though there is not any read or writeconflict. The cause of this is that speculative transaction configuration/selection is used. There are transactions optimized for a single transactional object, for 1..n and for n to unlimited. So based on the execution of the transaction, the system learns; it begins with a cheap one and upgrades to more expensive ones. Once it has learned, it will reuse this knowledge. It can be activated/deactivated using the speculative property on the TransactionFactory. In most cases it is best use the default value (enabled) so you get more out of performance.
Coordinated transactions and Transactors
----------------------------------------
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
If you need coordinated transactions across actors or threads then see `Transactors <transactors-scala>`_.
If you need coordinated transactions across actors or threads then see :ref:`transactors-scala`.
Configuring transactions
------------------------
^^^^^^^^^^^^^^^^^^^^^^^^
It's possible to configure transactions. The ``atomic`` method can take an implicit or explicit ``TransactionFactory``, which can determine properties of the transaction. A default transaction factory is used if none is specified explicitly or there is no implicit ``TransactionFactory`` in scope.
@ -311,7 +313,7 @@ Here's a similar example with an individual transaction factory for each instanc
}
Transaction lifecycle listeners
-------------------------------
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
It's possible to have code that will only run on the successful commit of a transaction, or when a transaction aborts. You can do this by adding ``deferred`` or ``compensating`` blocks to a transaction.
@ -329,7 +331,7 @@ It's possible to have code that will only run on the successful commit of a tran
}
Blocking transactions
---------------------
^^^^^^^^^^^^^^^^^^^^^
You can block in a transaction until a condition is met by using an explicit ``retry``. To use ``retry`` you also need to configure the transaction to allow explicit retries.
@ -383,7 +385,7 @@ Here is an example of using ``retry`` to block until an account has enough money
transferer.stop()
Alternative blocking transactions
---------------------------------
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
You can also have two alternative blocking transactions, one of which can succeed first, with ``either-orElse``.
@ -434,10 +436,9 @@ You can also have two alternative blocking transactions, one of which can succee
brancher.stop()
----
Transactional datastructures
============================
----------------------------
Akka provides two datastructures that are managed by the STM.
@ -511,26 +512,23 @@ Here is the same example using TransactionalMap:
}
// -> User("bill")
----
Persistent datastructures
=========================
-------------------------
Akka's STM should only be used with immutable data. This can be costly if you have large datastructures and are using a naive copy-on-write. In order to make working with immutable datastructures fast enough Scala provides what are called Persistent Datastructures. There are currently two different ones:
* HashMap (`scaladoc <http://www.scala-lang.org/api/current/scala/collection/immutable/HashMap.html>`_)
* Vector (`scaladoc <http://www.scala-lang.org/api/current/scala/collection/immutable/Vector.html>`_)
* HashMap (`scaladoc <http://www.scala-lang.org/api/current/scala/collection/immutable/HashMap.html>`__)
* Vector (`scaladoc <http://www.scala-lang.org/api/current/scala/collection/immutable/Vector.html>`__)
They are immutable and each update creates a completely new version but they are using clever structural sharing in order to make them almost as fast, for both read and update, as regular mutable datastructures.
This illustration is taken from Rich Hickey's presentation. Copyright Rich Hickey 2009.
.. image:: http://eclipsesource.com/blogs/wp-content/uploads/2009/12/clojure-trees.png
.. image:: ../images/clojure-trees.png
----
JTA integration
===============
---------------
The STM has JTA (Java Transaction API) integration. This means that it will, if enabled, hook in to JTA and start a JTA transaction when the STM transaction is started. It will also rollback the STM transaction if the JTA transaction has failed and vice versa. This does not mean that the STM is made durable, if you need that you should use one of the `persistence modules <persistence>`_. It simply means that the STM will participate and interact with and external JTA provider, for example send a message using JMS atomically within an STM transaction, or use Hibernate to persist STM managed data etc.
@ -556,9 +554,8 @@ You also have to configure which JTA provider to use etc in the 'jta' config sec
timeout = 60
}
----
Ants simulation sample
======================
----------------------
One fun and very enlightening visual demo of STM, actors and transactional references is the `Ant simulation sample <http://github.com/jboner/akka/tree/master/akka-samples/akka-sample-ants/>`_. I encourage you to run it and read through the code since it's a good example of using actors with STM.

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@ -40,6 +40,10 @@ encompass functional tests of complete actor networks. The important
distinction lies in whether concurrency concerns are part of the test or not.
The tools offered are described in detail in the following sections.
.. note::
Be sure to add the module :mod:`akka-testkit` to your dependencies.
Unit Testing with :class:`TestActorRef`
=======================================
@ -68,6 +72,8 @@ reference is done like this:
.. code-block:: scala
import akka.testkit.TestActorRef
val actorRef = TestActorRef[MyActor]
val actor = actorRef.underlyingActor
@ -169,6 +175,10 @@ common task easy:
.. code-block:: scala
import akka.testkit.TestKit
import org.scalatest.WordSpec
import org.scalatest.matchers.MustMatchers
class MySpec extends WordSpec with MustMatchers with TestKit {
"An Echo actor" must {
@ -252,6 +262,31 @@ runs everything which would normally be queued directly on the current thread,
the full history of a message's processing chain is recorded on the call stack,
so long as all intervening actors run on this dispatcher.
How to use it
-------------
Just set the dispatcher as you normally would, either from within the actor
.. code-block:: scala
import akka.testkit.CallingThreadDispatcher
class MyActor extends Actor {
self.dispatcher = CallingThreadDispatcher.global
...
}
or from the client code
.. code-block:: scala
val ref = Actor.actorOf[MyActor]
ref.dispatcher = CallingThreadDispatcher.global
ref.start()
As the :class:`CallingThreadDispatcher` does not have any configurable state,
you may always use the (lazily) preallocated one as shown in the examples.
How it works
------------

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@ -4,7 +4,7 @@
TestKit Example
###############
Ray Roestenburg's example code from `his blog <http://roestenburg.agilesquad.com/2011/02/unit-testing-akka-actors-with-testkit_12.html>`_.
Ray Roestenburg's example code from `his blog <http://roestenburg.agilesquad.com/2011/02/unit-testing-akka-actors-with-testkit_12.html>`_ adapted to work with Akka 1.1.
.. code-block:: scala
@ -14,7 +14,7 @@ Ray Roestenburg's example code from `his blog <http://roestenburg.agilesquad.com
import org.scalatest.{WordSpec, BeforeAndAfterAll}
import akka.actor.Actor._
import akka.util.duration._
import akka.util.TestKit
import akka.testkit.TestKit
import java.util.concurrent.TimeUnit
import akka.actor.{ActorRef, Actor}
import util.Random

View file

@ -1,10 +1,16 @@
**<span style="font-size: 150%;">Transactors (Scala)</span>**
=============================================================
.. _transactors-scala:
Transactors (Scala)
===================
.. sidebar:: Contents
.. contents:: :local:
Module stability: **SOLID**
Why Transactors?
================
----------------
Actors are excellent for solving problems where you have many independent processes that can work in isolation and only interact with other Actors through message passing. This model fits many problems. But the actor model is unfortunately a terrible model for implementing truly shared state. E.g. when you need to have consensus and a stable view of state across many components. The classic example is the bank account where clients can deposit and withdraw, in which each operation needs to be atomic. For detailed discussion on the topic see `this JavaOne presentation <http://www.slideshare.net/jboner/state-youre-doing-it-wrong-javaone-2009>`_.
@ -15,21 +21,21 @@ Akka's Transactors combine Actors and STM to provide the best of the Actor model
If you need Durability then you should not use one of the in-memory data structures but one of the persistent ones.
Generally, the STM is not needed very often when working with Akka. Some use-cases (that we can think of) are:
# When you really need composable message flows across many actors updating their **internal local** state but need them to do that atomically in one big transaction. Might not often, but when you do need this then you are screwed without it.
# When you want to share a datastructure across actors.
# When you need to use the persistence modules.
- When you really need composable message flows across many actors updating their **internal local** state but need them to do that atomically in one big transaction. Might not often, but when you do need this then you are screwed without it.
- When you want to share a datastructure across actors.
- When you need to use the persistence modules.
Actors and STM
--------------
^^^^^^^^^^^^^^
You can combine Actors and STM in several ways. An Actor may use STM internally so that particular changes are guaranteed to be atomic. Actors may also share transactional datastructures as the STM provides safe shared state across threads.
It's also possible to coordinate transactions across Actors or threads so that either the transactions in a set all commit successfully or they all fail. This is the focus of Transactors and the explicit support for coordinated transactions in this section.
----
Coordinated transactions
========================
------------------------
Akka provides an explicit mechanism for coordinating transactions across Actors. Under the hood it uses a ``CountDownCommitBarrier``, similar to a CountDownLatch.
@ -70,7 +76,7 @@ Here is an example of coordinating two simple counter Actors so that they both i
counter1.stop()
counter2.stop()
To start a new coordinated transaction set that you will also participate in, just create a ``Coordinated`` object:
To start a new coordinated transaction that you will also participate in, just create a ``Coordinated`` object:
.. code-block:: scala
@ -90,7 +96,7 @@ To receive a coordinated message in an actor simply match it in a case statement
case coordinated @ Coordinated(Message) => ...
}
To include another actor in the same coordinated transaction set that you've created or received, use the apply method on that object. This will increment the number of parties involved by one and create a new ``Coordinated`` object to be sent.
To include another actor in the same coordinated transaction that you've created or received, use the apply method on that object. This will increment the number of parties involved by one and create a new ``Coordinated`` object to be sent.
.. code-block:: scala
@ -106,10 +112,9 @@ To enter the coordinated transaction use the atomic method of the coordinated ob
The coordinated transaction will wait for the other transactions before committing. If any of the coordinated transactions fail then they all fail.
----
Transactor
==========
----------
Transactors are actors that provide a general pattern for coordinating transactions, using the explicit coordination described above.
@ -125,7 +130,7 @@ Here's an example of a simple transactor that will join a coordinated transactio
class Counter extends Transactor {
val count = Ref(0)
def atomically = {
override def atomically = {
case Increment => count alter (_ + 1)
}
}
@ -140,6 +145,7 @@ Example of coordinating an increment:
import akka.transactor.Transactor
import akka.stm.Ref
import akka.actor.ActorRef
case object Increment
@ -150,7 +156,7 @@ Example of coordinating an increment:
case Increment => include(friend)
}
def atomically = {
override def atomically = {
case Increment => count alter (_ + 1)
}
}
@ -176,10 +182,9 @@ To execute directly before or after the coordinated transaction, override the ``
To completely bypass coordinated transactions override the ``normally`` method. Any message matched by ``normally`` will not be matched by the other methods, and will not be involved in coordinated transactions. In this method you can implement normal actor behavior, or use the normal STM atomic for local transactions.
----
Coordinating Typed Actors
=========================
-------------------------
It's also possible to use coordinated transactions with typed actors. You can explicitly pass around ``Coordinated`` objects, or use built-in support with the ``@Coordinated`` annotation and the ``Coordination.coordinate`` method.
@ -188,7 +193,7 @@ To specify a method should use coordinated transactions add the ``@Coordinated``
.. code-block:: scala
trait Counter {
@Coordinated def increment: Unit
@Coordinated def increment()
def get: Int
}
@ -197,8 +202,8 @@ To coordinate transactions use a ``coordinate`` block:
.. code-block:: scala
coordinate {
counter1.increment
counter2.increment
counter1.increment()
counter2.increment()
}
Here's an example of using ``@Coordinated`` with a TypedActor to coordinate increments.
@ -211,13 +216,13 @@ Here's an example of using ``@Coordinated`` with a TypedActor to coordinate incr
import akka.transactor.Coordination._
trait Counter {
@Coordinated def increment: Unit
@Coordinated def increment()
def get: Int
}
class CounterImpl extends TypedActor with Counter {
val ref = Ref(0)
def increment = ref alter (_ + 1)
def increment() { ref alter (_ + 1) }
def get = ref.get
}
@ -227,8 +232,8 @@ Here's an example of using ``@Coordinated`` with a TypedActor to coordinate incr
val counter2 = TypedActor.newInstance(classOf[Counter], classOf[CounterImpl])
coordinate {
counter1.increment
counter2.increment
counter1.increment()
counter2.increment()
}
TypedActor.stop(counter1)
@ -236,9 +241,10 @@ Here's an example of using ``@Coordinated`` with a TypedActor to coordinate incr
The ``coordinate`` block will wait for the transactions to complete. If you do not want to wait then you can specify this explicitly:
`<code format="scala">`_
coordinate(wait = false) {
counter1.increment
counter2.increment
}
`<code>`_
.. code-block:: scala
coordinate(wait = false) {
counter1.increment()
counter2.increment()
}

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@ -1,6 +1,10 @@
Tutorial: write a scalable, fault-tolerant, persistent network chat server and client (Scala)
Tutorial: write a scalable, fault-tolerant, network chat server and client (Scala)
=============================================================================================
.. sidebar:: Contents
.. contents:: :local:
Introduction
------------
@ -44,6 +48,8 @@ Here is a little example before we dive into a more interesting one.
.. code-block:: scala
import akka.actor.Actor
class MyActor extends Actor {
def receive = {
case "test" => println("received test")
@ -81,12 +87,53 @@ We will try to write a simple chat/IM system. It is client-server based and uses
We will use many of the features of Akka along the way. In particular; Actors, fault-tolerance using Actor supervision, remote Actors, Software Transactional Memory (STM) and persistence.
But let's start by defining the messages that will flow in our system.
Creating an Akka SBT project
----------------------------
First we need to create an SBT project for our tutorial. You do that by stepping into the directory you want to create your project in and invoking the ``sbt`` command answering the questions for setting up your project::
$ sbt
Project does not exist, create new project? (y/N/s) y
Name: Chat
Organization: Hakkers Inc
Version [1.0]:
Scala version [2.9.0.RC1]:
sbt version [0.7.6.RC0]:
Add the Akka SBT plugin definition to your SBT project by creating a ``Plugins.scala`` file in the ``project/plugins`` directory containing::
import sbt._
class Plugins(info: ProjectInfo) extends PluginDefinition(info) {
val akkaRepo = "Akka Repo" at "http://akka.io/repository"
val akkaPlugin = "se.scalablesolutions.akka" % "akka-sbt-plugin" % "1.1-M1"
}
Create a project definition ``project/build/Project.scala`` file containing::
import sbt._
class ChatProject(info: ProjectInfo) extends DefaultProject(info) with AkkaProject {
val akkaRepo = "Akka Repo" at "http://akka.io/repository"
val akkaSTM = akkaModule("stm")
val akkaRemote = akkaModule("remote")
}
Make SBT download the dependencies it needs. That is done by invoking::
> reload
> update
From the SBT project you can generate files for your IDE:
- `SbtEclipsify <https://github.com/musk/SbtEclipsify>`_ to generate Eclipse project. Detailed instructions are available in :ref:`getting-started-first-scala-eclipse`.
- `sbt-idea <https://github.com/mpeltonen/sbt-idea>`_ to generate IntelliJ IDEA project.
Creating messages
-----------------
It is very important that all messages that will be sent around in the system are immutable. The Actor model relies on the simple fact that no state is shared between Actors and the only way to guarantee that is to make sure we don't pass mutable state around as part of the messages.
Let's start by defining the messages that will flow in our system. It is very important that all messages that will be sent around in the system are immutable. The Actor model relies on the simple fact that no state is shared between Actors and the only way to guarantee that is to make sure we don't pass mutable state around as part of the messages.
In Scala we have something called `case classes <http://www.scala-lang.org/node/107>`_. These make excellent messages since they are both immutable and great to pattern match on.
@ -118,7 +165,8 @@ Sometimes however, there is a need for sequential logic, sending a message and w
def login = chat ! Login(name)
def logout = chat ! Logout(name)
def post(message: String) = chat ! ChatMessage(name, name + ": " + message)
def chatLog = (chat !! GetChatLog(name)).as[ChatLog].getOrElse(throw new Exception("Couldn't get the chat log from ChatServer"))
def chatLog = (chat !! GetChatLog(name)).as[ChatLog]
.getOrElse(throw new Exception("Couldn't get the chat log from ChatServer"))
}
As you can see, we are using the 'Actor.remote.actorFor' to lookup the chat server on the remote node. From this call we will get a handle to the remote instance and can use it as it is local.
@ -221,7 +269,7 @@ I'll try to show you how we can make use Scala's mixins to decouple the Actor im
protected def sessionManagement: Receive
protected def shutdownSessions(): Unit
override def postStop = {
override def postStop() = {
EventHandler.info(this, "Chat server is shutting down...")
shutdownSessions
self.unlink(storage)
@ -422,7 +470,7 @@ We have now created the full functionality for the chat server, all nicely decou
SessionManagement with
ChatManagement with
MemoryChatStorageFactory {
override def preStart = {
override def preStart() = {
remote.start("localhost", 2552);
remote.register("chat:service", self) //Register the actor with the specified service id
}

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