stashin commit so Iulian can play with it

.gitignore

@@ -64,3 +64,4 @@ mongoDB/
 redis/
 beanstalk/
 .scalastyle
+bin/

akka-actor/src/main/java/akka/japi/JAPI.java

@@ -0,0 +1,11 @@
+package akka.japi;
+
+import scala.collection.Seq;
+
+public class JAPI {
+
+  public static <T> Seq<T> seq(T... ts) {
+    return Util.arrayToSeq(ts);
+  }
+  
+}

akka-actor/src/main/scala/akka/japi/JavaAPI.scala

@@ -5,6 +5,7 @@
 package akka.japi
 
 import scala.Some
+import scala.util.control.NoStackTrace
 
 /**
  * A Function interface. Used to create first-class-functions is Java.
@@ -44,6 +45,50 @@ trait Creator[T] {
   def create(): T
 }
 
+object PurePartialFunction {
+  case object NoMatch extends RuntimeException with NoStackTrace
+}
+
+/**
+ * Helper for implementing a *pure* partial function: it will possibly be
+ * invoked multiple times for a single “application”, because its only abstract
+ * method is used for both isDefinedAt() and apply(); the former is mapped to
+ * `isCheck == true` and the latter to `isCheck == false` for those cases where
+ * this is important to know.
+ *
+ * {{{
+ * new PurePartialFunction<Object, String>() {
+ *   public String apply(Object in, boolean isCheck) {
+ *     if (in instanceof TheThing) {
+ *       if (isCheck) return null; // to spare the expensive or side-effecting code
+ *       return doSomethingWithTheThing((TheThing) in);
+ *     } else {
+ *       throw noMatch();
+ *     }
+ *   }
+ * }
+ * }}}
+ *
+ * The typical use of partial functions from Akka looks like the following:
+ *
+ * {{{
+ * if (pf.isDefinedAt(x)) pf.apply(x)
+ * }}}
+ *
+ * i.e. it will first call `PurePartialFunction.apply(x, true)` and if that
+ * does not throw `noMatch()` it will continue with calling
+ * `PurePartialFunction.apply(x, false)`.
+ */
+abstract class PurePartialFunction[A, B] extends scala.runtime.AbstractFunction1[A, B] with PartialFunction[A, B] {
+  import PurePartialFunction._
+
+  def apply(x: A, isCheck: Boolean): B
+
+  final def isDefinedAt(x: A): Boolean = try { apply(x, true); true } catch { case NoMatch ⇒ false }
+  final def apply(x: A): B = try apply(x, false) catch { case NoMatch ⇒ throw new MatchError }
+  final def noMatch(): RuntimeException = NoMatch
+}
+
 /**
  * This class represents optional values. Instances of <code>Option</code>
  * are either instances of case class <code>Some</code> or it is case
@@ -117,4 +162,6 @@ object Util {
    * Given a Class returns a Scala Manifest of that Class
    */
   def manifest[T](clazz: Class[T]): Manifest[T] = Manifest.classType(clazz)
+
+  def arrayToSeq[T](arr: Array[T]): Seq[T] = arr.toSeq
 }

akka-docs/java/code/docs/testkit/TestKitDocTest.java

@@ -0,0 +1,131 @@
+/*
+ * 
+ */
+package docs.testkit;
+
+import static org.junit.Assert.*;
+
+import org.junit.AfterClass;
+import org.junit.Test;
+
+import akka.actor.ActorSystem;
+import akka.actor.Props;
+import akka.actor.UntypedActor;
+import akka.dispatch.Await;
+import akka.dispatch.Future;
+import akka.japi.JAPI;
+import akka.japi.PurePartialFunction;
+import akka.testkit.TestActorRef;
+import akka.testkit.TestKit;
+import akka.util.Duration;
+
+public class TestKitDocTest {
+  
+  //#test-actor-ref
+  static class MyActor extends UntypedActor {
+    public void onReceive(Object o) throws Exception {
+      if (o.equals("say42")) {
+        getSender().tell(42, getSelf());
+      } else if (o instanceof Exception) {
+        throw (Exception) o;
+      }
+    }
+    public boolean testMe() { return true; }
+  }
+  
+  //#test-actor-ref
+  
+  private static ActorSystem system;
+  
+  public TestKitDocTest() {
+    system = ActorSystem.create();
+  }
+  
+  @AfterClass
+  public static void cleanup() {
+    system.shutdown();
+  }
+
+  //#test-actor-ref
+  @Test
+  public void demonstrateTestActorRef() {
+    final Props props = new Props(MyActor.class);
+    final TestActorRef<MyActor> ref = TestActorRef.apply(props, system);
+    final MyActor actor = ref.underlyingActor();
+    assertTrue(actor.testMe());
+  }
+  //#test-actor-ref
+  
+  //#test-behavior
+  @Test
+  public void demonstrateAsk() throws Exception {
+    final Props props = new Props(MyActor.class);
+    final TestActorRef<MyActor> ref = TestActorRef.apply(props, system);
+    final Future<Object> future = akka.pattern.Patterns.ask(ref, "say42", 3000);
+    assertTrue(future.isCompleted());
+    assertEquals(42, Await.result(future, Duration.Zero()));
+  }
+  //#test-behavior
+  
+  //#test-expecting-exceptions
+  @Test
+  public void demonstrateExceptions() {
+    final Props props = new Props(MyActor.class);
+    final TestActorRef<MyActor> ref = TestActorRef.apply(props, system);
+    try {
+      ref.receive(new Exception("expected"));
+      fail("expected an exception to be thrown");
+    } catch (Exception e) {
+      assertEquals("expected", e.getMessage());
+    }
+  }
+  //#test-expecting-exceptions
+  
+  //#test-within
+  @Test
+  public void demonstrateWithin() {
+    new TestKit(system) {{
+      testActor().tell(42);
+      new Within(Duration.parse("1 second")) {
+        // do not put code outside this method, will run afterwards
+        public void run() {
+          assertEquals((Integer) 42, expectMsgClass(Integer.class));
+        }
+      };
+    }};
+  }
+  //#test-within
+  
+  @Test
+  public void demonstrateExpectMsgPF() {
+    new TestKit(system) {{
+      testActor().tell(42);
+      //#test-expect-pf
+      final String out = expectMsgPF(Duration.parse("1 second"), "fourty-two",
+        new PurePartialFunction<Object, String>() {
+          public String apply(Object in, boolean isCheck) {
+            if (Integer.valueOf(42).equals(in)) {
+              return "match";
+            } else {
+              throw noMatch();
+            }
+          }
+        }
+      );
+      assertEquals("match", out);
+      //#test-expect-pf
+      testActor().tell("world");
+      //#test-expect-anyof
+      final String any = expectMsgAnyOf(remaining(), JAPI.seq("hello", "world"));
+      //#test-expect-anyof
+      assertEquals("world", any);
+      testActor().tell("world");
+      //#test-expect-anyclassof
+      @SuppressWarnings("unchecked")
+      final String anyClass = expectMsgAnyClassOf(remaining(), JAPI.<Class<? extends String>>seq(String.class));
+      //#test-expect-anyclassof
+      assertEquals("world", any);
+    }};
+  }
+  
+}

akka-docs/java/testing.rst

@@ -4,11 +4,696 @@
 Testing Actor Systems (Java)
 ##############################
 
-Due to the conciseness of test DSLs available for Scala, it may be a good idea
+As with any piece of software, automated tests are a very important part of the
-to write the test suite in that language even if the main project is written in
+development cycle. The actor model presents a different view on how units of
-Java. If that is not desirable, you can also use :class:`TestKit` and friends
+code are delimited and how they interact, which has an influence on how to
-from Java, albeit with more verbose syntax Munish Gupta has `published a nice
+perform tests.
-post <http://www.akkaessentials.in/2012/05/using-testkit-with-java.html>`_
+
-showing several patterns you may find useful, and for reference documentation
+.. note::
-please refer to :ref:`akka-testkit` until that section has been ported over to
+
-cover Java in full.
+  Due to the conciseness of test DSLs available for Scala (`ScalaTest`_,
+  `Specs2`_, `ScalaCheck`_), it may be a good idea to write the test suite in
+  that language even if the main project is written in Java. If that is not
+  desirable, you can also use :class:`TestKit` and friends from Java, albeit
+  with more verbose syntax which is covered below. Munish Gupta has `published
+  a nice post
+  <http://www.akkaessentials.in/2012/05/using-testkit-with-java.html>`_ showing
+  several patterns you may find useful.
+
+.. _ScalaTest:  http://scalatest.org/
+.. _Specs2:     http://specs2.org/
+.. _ScalaCheck: http://code.google.com/p/scalacheck/
+
+Akka comes with a dedicated module :mod:`akka-testkit` for supporting tests at
+different levels, which fall into two clearly distinct categories:
+
+ - Testing isolated pieces of code without involving the actor model, meaning
+   without multiple threads; this implies completely deterministic behavior
+   concerning the ordering of events and no concurrency concerns and will be
+   called **Unit Testing** in the following.
+ - Testing (multiple) encapsulated actors including multi-threaded scheduling;
+   this implies non-deterministic order of events but shielding from
+   concurrency concerns by the actor model and will be called **Integration
+   Testing** in the following.
+
+There are of course variations on the granularity of tests in both categories,
+where unit testing reaches down to white-box tests and integration testing can
+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`
+=======================================
+
+Testing the business logic inside :class:`Actor` classes can be divided into
+two parts: first, each atomic operation must work in isolation, then sequences
+of incoming events must be processed correctly, even in the presence of some
+possible variability in the ordering of events. The former is the primary use
+case for single-threaded unit testing, while the latter can only be verified in
+integration tests.
+
+Normally, the :class:`ActorRef` shields the underlying :class:`Actor` instance
+from the outside, the only communications channel is the actor's mailbox. This
+restriction is an impediment to unit testing, which led to the inception of the
+:class:`TestActorRef`. This special type of reference is designed specifically
+for test purposes and allows access to the actor in two ways: either by
+obtaining a reference to the underlying actor instance, or by invoking or
+querying the actor's behaviour (:meth:`receive`). Each one warrants its own
+section below.
+
+Obtaining a Reference to an :class:`Actor`
+------------------------------------------
+
+Having access to the actual :class:`Actor` object allows application of all
+traditional unit testing techniques on the contained methods. Obtaining a
+reference is done like this:
+
+.. includecode:: code/docs/testkit/TestKitDocTest.java#test-actor-ref
+
+Since :class:`TestActorRef` is generic in the actor type it returns the
+underlying actor with its proper static type. From this point on you may bring
+any unit testing tool to bear on your actor as usual.
+
+Testing the Actor's Behavior
+----------------------------
+
+When the dispatcher invokes the processing behavior of an actor on a message,
+it actually calls :meth:`apply` on the current behavior registered for the
+actor. This starts out with the return value of the declared :meth:`receive`
+method, but it may also be changed using :meth:`become` and :meth:`unbecome` in
+response to external messages. All of this contributes to the overall actor
+behavior and it does not lend itself to easy testing on the :class:`Actor`
+itself. Therefore the :class:`TestActorRef` offers a different mode of
+operation to complement the :class:`Actor` testing: it supports all operations
+also valid on normal :class:`ActorRef`. Messages sent to the actor are
+processed synchronously on the current thread and answers may be sent back as
+usual. This trick is made possible by the :class:`CallingThreadDispatcher`
+described below (see `CallingThreadDispatcher`_); this dispatcher is set
+implicitly for any actor instantiated into a :class:`TestActorRef`.
+
+.. includecode:: code/docs/testkit/TestKitDocTest.java#test-behavior
+
+As the :class:`TestActorRef` is a subclass of :class:`LocalActorRef` with a few
+special extras, also aspects like supervision and restarting work properly, but
+beware that execution is only strictly synchronous as long as all actors
+involved use the :class:`CallingThreadDispatcher`. As soon as you add elements
+which include more sophisticated scheduling you leave the realm of unit testing
+as you then need to think about asynchronicity again (in most cases the problem
+will be to wait until the desired effect had a chance to happen).
+
+One more special aspect which is overridden for single-threaded tests is the
+:meth:`receiveTimeout`, as including that would entail asynchronous queuing of
+:obj:`ReceiveTimeout` messages, violating the synchronous contract.
+
+.. warning::
+
+   To summarize: :class:`TestActorRef` overwrites two fields: it sets the
+   dispatcher to :obj:`CallingThreadDispatcher.global` and it sets the
+   :obj:`receiveTimeout` to None.
+
+The Way In-Between: Expecting Exceptions
+----------------------------------------
+
+If you want to test the actor behavior, including hotswapping, but without
+involving a dispatcher and without having the :class:`TestActorRef` swallow
+any thrown exceptions, then there is another mode available for you: just use
+the :meth:`receive` method :class:`TestActorRef`, which will be forwarded to the
+underlying actor:
+
+.. includecode:: code/docs/testkit/TestKitDocTest.java#test-expecting-exceptions
+
+Use Cases
+---------
+
+You may of course mix and match both modi operandi of :class:`TestActorRef` as
+suits your test needs:
+
+ - one common use case is setting up the actor into a specific internal state
+   before sending the test message
+ - another is to verify correct internal state transitions after having sent
+   the test message
+
+Feel free to experiment with the possibilities, and if you find useful
+patterns, don't hesitate to let the Akka forums know about them! Who knows,
+common operations might even be worked into nice DSLs.
+
+Integration Testing with :class:`TestKit`
+=========================================
+
+When you are reasonably sure that your actor's business logic is correct, the
+next step is verifying that it works correctly within its intended environment
+(if the individual actors are simple enough, possibly because they use the
+:mod:`FSM` module, this might also be the first step). The definition of the
+environment depends of course very much on the problem at hand and the level at
+which you intend to test, ranging for functional/integration tests to full
+system tests. The minimal setup consists of the test procedure, which provides
+the desired stimuli, the actor under test, and an actor receiving replies.
+Bigger systems replace the actor under test with a network of actors, apply
+stimuli at varying injection points and arrange results to be sent from
+different emission points, but the basic principle stays the same in that a
+single procedure drives the test.
+
+The :class:`TestKit` class contains a collection of tools which makes this
+common task easy.
+
+.. includecode:: code/docs/testkit/PlainWordTest.java#plain-spec
+
+The :class:`TestKit` contains an actor named :obj:`testActor` which is the
+entry point for messages to be examined with the various ``expectMsg...``
+assertions detailed below. When mixing in the trait ``ImplicitSender`` this
+test actor is implicitly used as sender reference when dispatching messages
+from the test procedure. The :obj:`testActor` may also be passed to
+other actors as usual, usually subscribing it as notification listener. There
+is a whole set of examination methods, e.g. receiving all consecutive messages
+matching certain criteria, receiving a whole sequence of fixed messages or
+classes, receiving nothing for some time, etc.
+
+The ActorSystem passed in to the constructor of TestKit is accessible via the
+:meth:`system()` method.  Remember to shut down the actor system after the test
+is finished (also in case of failure) so that all actors—including the test
+actor—are stopped.
+
+Built-In Assertions
+-------------------
+
+The above mentioned :meth:`expectMsg` is not the only method for formulating
+assertions concerning received messages. Here is the full list:
+
+  * :meth:`<T> T expectMsg(Duration d, T msg): T`
+
+    The given message object must be received within the specified time; the
+    object will be returned.
+
+  * :meth:`<T> T expectMsgPF(Duration d, PartialFunction<Object, T> pf)`
+
+    Within the given time period, a message must be received and the given
+    partial function must be defined for that message; the result from applying
+    the partial function to the received message is returned.
+
+    .. includecode:: code/docs/testkit/TestKitDocTest.java#test-expect-pf
+
+  * :meth:`<T> T expectMsgClass(Duration d, Class<T> c)`
+
+    An object which is an instance of the given :class:`Class` must be received
+    within the allotted time frame; the object will be returned. Note that this
+    does a conformance check; if you need the class to be equal, have a look at
+    :meth:`expectMsgAllClassOf` with a single given class argument.
+
+  * :meth:`<T> T expectMsgAnyOf(Duration d, Seq<T> obj)`
+
+    An object must be received within the given time, and it must be equal (
+    compared with ``equals()``) to at least one of the passed reference objects; the
+    received object will be returned.
+
+    .. includecode:: code/docs/testkit/TestKitDocTest.java#test-expect-anyof
+
+  * :meth:`<T> T expectMsgAnyClassOf(Duration d, Seq<Class<? extends T>> classes)`
+
+    An object must be received within the given time, and it must be an
+    instance of at least one of the supplied :class:`Class` objects; the
+    received object will be returned.
+
+    .. includecode:: code/docs/testkit/TestKitDocTest.java#test-expect-anyclassof
+
+  * :meth:`expectMsgAllOf[T](d: Duration, obj: T*): Seq[T]`
+
+    A number of objects matching the size of the supplied object array must be
+    received within the given time, and for each of the given objects there
+    must exist at least one among the received ones which equals (compared with
+    ``==``) it. The full sequence of received objects is returned.
+
+  * :meth:`expectMsgAllClassOf[T](d: Duration, c: Class[_ <: T]*): Seq[T]`
+
+    A number of objects matching the size of the supplied :class:`Class` array
+    must be received within the given time, and for each of the given classes
+    there must exist at least one among the received objects whose class equals
+    (compared with ``==``) it (this is *not* a conformance check). The full
+    sequence of received objects is returned.
+
+  * :meth:`expectMsgAllConformingOf[T](d: Duration, c: Class[_ <: T]*): Seq[T]`
+
+    A number of objects matching the size of the supplied :class:`Class` array
+    must be received within the given time, and for each of the given classes
+    there must exist at least one among the received objects which is an
+    instance of this class. The full sequence of received objects is returned.
+
+  * :meth:`expectNoMsg(d: Duration)`
+
+    No message must be received within the given time. This also fails if a
+    message has been received before calling this method which has not been
+    removed from the queue using one of the other methods.
+
+  * :meth:`receiveN(n: Int, d: Duration): Seq[AnyRef]`
+
+    ``n`` messages must be received within the given time; the received
+    messages are returned.
+
+  * :meth:`fishForMessage(max: Duration, hint: String)(pf: PartialFunction[Any, Boolean]): Any`
+
+    Keep receiving messages as long as the time is not used up and the partial
+    function matches and returns ``false``. Returns the message received for
+    which it returned ``true`` or throws an exception, which will include the
+    provided hint for easier debugging.
+
+In addition to message reception assertions there are also methods which help
+with message flows:
+
+  * :meth:`receiveOne(d: Duration): AnyRef`
+
+    Tries to receive one message for at most the given time interval and
+    returns ``null`` in case of failure. If the given Duration is zero, the
+    call is non-blocking (polling mode).
+
+  * :meth:`receiveWhile[T](max: Duration, idle: Duration, messages: Int)(pf: PartialFunction[Any, T]): Seq[T]`
+
+    Collect messages as long as
+
+    * they are matching the given partial function
+    * the given time interval is not used up
+    * the next message is received within the idle timeout
+    * the number of messages has not yet reached the maximum
+
+    All collected messages are returned. The maximum duration defaults to the
+    time remaining in the innermost enclosing :ref:`within <TestKit.within>`
+    block and the idle duration defaults to infinity (thereby disabling the
+    idle timeout feature). The number of expected messages defaults to
+    ``Int.MaxValue``, which effectively disables this limit.
+
+  * :meth:`awaitCond(p: => Boolean, max: Duration, interval: Duration)`
+
+    Poll the given condition every :obj:`interval` until it returns ``true`` or
+    the :obj:`max` duration is used up. The interval defaults to 100 ms and the
+    maximum defaults to the time remaining in the innermost enclosing
+    :ref:`within <TestKit.within>` block.
+
+  * :meth:`ignoreMsg(pf: PartialFunction[AnyRef, Boolean])`
+
+    :meth:`ignoreNoMsg`
+
+    The internal :obj:`testActor` contains a partial function for ignoring
+    messages: it will only enqueue messages which do not match the function or
+    for which the function returns ``false``. This function can be set and
+    reset using the methods given above; each invocation replaces the previous
+    function, they are not composed.
+
+    This feature is useful e.g. when testing a logging system, where you want
+    to ignore regular messages and are only interested in your specific ones.
+
+Expecting Exceptions
+--------------------
+
+Since an integration test does not allow to the internal processing of the
+participating actors, verifying expected exceptions cannot be done directly.
+Instead, use the logging system for this purpose: replacing the normal event
+handler with the :class:`TestEventListener` and using an :class:`EventFilter`
+allows assertions on log messages, including those which are generated by
+exceptions:
+
+.. includecode:: code/docs/testkit/TestKitDocTest.java#event-filter
+
+.. _TestKit.within:
+
+Timing Assertions
+-----------------
+
+Another important part of functional testing concerns timing: certain events
+must not happen immediately (like a timer), others need to happen before a
+deadline. Therefore, all examination methods accept an upper time limit within
+the positive or negative result must be obtained. Lower time limits need to be
+checked external to the examination, which is facilitated by a new construct
+for managing time constraints:
+
+.. code-block:: scala
+
+   within([min, ]max) {
+     ...
+   }
+
+The block given to :meth:`within` must complete after a :ref:`Duration` which
+is between :obj:`min` and :obj:`max`, where the former defaults to zero. The
+deadline calculated by adding the :obj:`max` parameter to the block's start
+time is implicitly available within the block to all examination methods, if
+you do not specify it, is is inherited from the innermost enclosing
+:meth:`within` block.
+
+It should be noted that if the last message-receiving assertion of the block is
+:meth:`expectNoMsg` or :meth:`receiveWhile`, the final check of the
+:meth:`within` is skipped in order to avoid false positives due to wake-up
+latencies. This means that while individual contained assertions still use the
+maximum time bound, the overall block may take arbitrarily longer in this case.
+
+.. includecode:: code/docs/testkit/TestKitDocTest.java#test-within
+
+.. note::
+
+   All times are measured using ``System.nanoTime``, meaning that they describe
+   wall time, not CPU time.
+
+Ray Roestenburg has written a great article on using the TestKit:
+`<http://roestenburg.agilesquad.com/2011/02/unit-testing-akka-actors-with-testkit_12.html>`_.
+His full example is also available :ref:`here <testkit-example>`.
+
+Accounting for Slow Test Systems
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The tight timeouts you use during testing on your lightning-fast notebook will
+invariably lead to spurious test failures on the heavily loaded Jenkins server
+(or similar). To account for this situation, all maximum durations are
+internally scaled by a factor taken from the :ref:`configuration`,
+``akka.test.timefactor``, which defaults to 1.
+
+You can scale other durations with the same factor by using the implicit conversion
+in ``akka.testkit`` package object to add dilated function to :class:`Duration`.
+
+.. includecode:: code/docs/testkit/TestKitDocTest.java#duration-dilation
+
+Resolving Conflicts with Implicit ActorRef
+------------------------------------------
+
+If you want the sender of messages inside your TestKit-based tests to be the ``testActor``
+simply mix in ``ÌmplicitSender`` into your test.
+
+.. includecode:: code/docs/testkit/PlainWordSpec.scala#implicit-sender
+
+Using Multiple Probe Actors
+---------------------------
+
+When the actors under test are supposed to send various messages to different
+destinations, it may be difficult distinguishing the message streams arriving
+at the :obj:`testActor` when using the :class:`TestKit` as a mixin. Another
+approach is to use it for creation of simple probe actors to be inserted in the
+message flows. To make this more powerful and convenient, there is a concrete
+implementation called :class:`TestProbe`. The functionality is best explained
+using a small example:
+
+.. includecode:: code/docs/testkit/TestKitDocTest.java
+   :include: imports-test-probe,my-double-echo,test-probe
+
+Here a the system under test is simulated by :class:`MyDoubleEcho`, which is
+supposed to mirror its input to two outputs. Attaching two test probes enables
+verification of the (simplistic) behavior. Another example would be two actors
+A and B which collaborate by A sending messages to B. In order to verify this
+message flow, a :class:`TestProbe` could be inserted as target of A, using the
+forwarding capabilities or auto-pilot described below to include a real B in
+the test setup.
+
+Probes may also be equipped with custom assertions to make your test code even
+more concise and clear:
+
+.. includecode:: code/docs/testkit/TestKitDocTest.java
+   :include: test-special-probe
+
+You have complete flexibility here in mixing and matching the :class:`TestKit`
+facilities with your own checks and choosing an intuitive name for it. In real
+life your code will probably be a bit more complicated than the example given
+above; just use the power!
+
+Replying to Messages Received by Probes
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The probes keep track of the communications channel for replies, if possible,
+so they can also reply:
+
+.. includecode:: code/docs/testkit/TestKitDocTest.java#test-probe-reply
+
+Forwarding Messages Received by Probes
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Given a destination actor ``dest`` which in the nominal actor network would
+receive a message from actor ``source``. If you arrange for the message to be
+sent to a :class:`TestProbe` ``probe`` instead, you can make assertions
+concerning volume and timing of the message flow while still keeping the
+network functioning:
+
+.. includecode:: code/docs/testkit/TestKitDocTest.java
+   :include: test-probe-forward-actors,test-probe-forward
+
+The ``dest`` actor will receive the same message invocation as if no test probe
+had intervened.
+
+Auto-Pilot
+^^^^^^^^^^
+
+Receiving messages in a queue for later inspection is nice, but in order to
+keep a test running and verify traces later you can also install an
+:class:`AutoPilot` in the participating test probes (actually in any
+:class:`TestKit`) which is invoked before enqueueing to the inspection queue.
+This code can be used to forward messages, e.g. in a chain ``A --> Probe -->
+B``, as long as a certain protocol is obeyed.
+
+.. includecode:: ../../akka-testkit/src/test/scala/akka/testkit/TestProbeSpec.scala#autopilot
+
+The :meth:`run` method must return the auto-pilot for the next message, wrapped
+in an :class:`Option`; setting it to :obj:`None` terminates the auto-pilot.
+
+Caution about Timing Assertions
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The behavior of :meth:`within` blocks when using test probes might be perceived
+as counter-intuitive: you need to remember that the nicely scoped deadline as
+described :ref:`above <TestKit.within>` is local to each probe. Hence, probes
+do not react to each other's deadlines or to the deadline set in an enclosing
+:class:`TestKit` instance::
+
+  class SomeTest extends TestKit(_system: ActorSystem) with ImplicitSender {
+
+    val probe = TestProbe()
+
+    within(100 millis) {
+      probe.expectMsg("hallo")  // Will hang forever!
+    }
+  }
+
+This test will hang indefinitely, because the :meth:`expectMsg` call does not
+see any deadline. Currently, the only option is to use ``probe.within`` in the
+above code to make it work; later versions may include lexically scoped
+deadlines using implicit arguments.
+
+.. _TestCallingThreadDispatcherRef:
+
+CallingThreadDispatcher
+=======================
+
+The :class:`CallingThreadDispatcher` serves good purposes in unit testing, as
+described above, but originally it was conceived in order to allow contiguous
+stack traces to be generated in case of an error. As this special dispatcher
+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:
+
+.. includecode:: code/docs/testkit/TestKitDocTest.java#calling-thread-dispatcher
+
+How it works
+------------
+
+When receiving an invocation, the :class:`CallingThreadDispatcher` checks
+whether the receiving actor is already active on the current thread. The
+simplest example for this situation is an actor which sends a message to
+itself. In this case, processing cannot continue immediately as that would
+violate the actor model, so the invocation is queued and will be processed when
+the active invocation on that actor finishes its processing; thus, it will be
+processed on the calling thread, but simply after the actor finishes its
+previous work. In the other case, the invocation is simply processed
+immediately on the current thread. Futures scheduled via this dispatcher are
+also executed immediately.
+
+This scheme makes the :class:`CallingThreadDispatcher` work like a general
+purpose dispatcher for any actors which never block on external events.
+
+In the presence of multiple threads it may happen that two invocations of an
+actor running on this dispatcher happen on two different threads at the same
+time. In this case, both will be processed directly on their respective
+threads, where both compete for the actor's lock and the loser has to wait.
+Thus, the actor model is left intact, but the price is loss of concurrency due
+to limited scheduling. In a sense this is equivalent to traditional mutex style
+concurrency.
+
+The other remaining difficulty is correct handling of suspend and resume: when
+an actor is suspended, subsequent invocations will be queued in thread-local
+queues (the same ones used for queuing in the normal case). The call to
+:meth:`resume`, however, is done by one specific thread, and all other threads
+in the system will probably not be executing this specific actor, which leads
+to the problem that the thread-local queues cannot be emptied by their native
+threads. Hence, the thread calling :meth:`resume` will collect all currently
+queued invocations from all threads into its own queue and process them.
+
+Limitations
+-----------
+
+If an actor's behavior blocks on a something which would normally be affected
+by the calling actor after having sent the message, this will obviously
+dead-lock when using this dispatcher. This is a common scenario in actor tests
+based on :class:`CountDownLatch` for synchronization:
+
+.. code-block:: scala
+
+   val latch = new CountDownLatch(1)
+   actor ! startWorkAfter(latch)   // actor will call latch.await() before proceeding
+   doSomeSetupStuff()
+   latch.countDown()
+
+The example would hang indefinitely within the message processing initiated on
+the second line and never reach the fourth line, which would unblock it on a
+normal dispatcher.
+
+Thus, keep in mind that the :class:`CallingThreadDispatcher` is not a
+general-purpose replacement for the normal dispatchers. On the other hand it
+may be quite useful to run your actor network on it for testing, because if it
+runs without dead-locking chances are very high that it will not dead-lock in
+production.
+
+.. warning::
+
+   The above sentence is unfortunately not a strong guarantee, because your
+   code might directly or indirectly change its behavior when running on a
+   different dispatcher. If you are looking for a tool to help you debug
+   dead-locks, the :class:`CallingThreadDispatcher` may help with certain error
+   scenarios, but keep in mind that it has may give false negatives as well as
+   false positives.
+
+Benefits
+--------
+
+To summarize, these are the features with the :class:`CallingThreadDispatcher`
+has to offer:
+
+ - Deterministic execution of single-threaded tests while retaining nearly full
+   actor semantics
+ - Full message processing history leading up to the point of failure in
+   exception stack traces
+ - Exclusion of certain classes of dead-lock scenarios
+
+.. _actor.logging:
+
+Tracing Actor Invocations
+=========================
+
+The testing facilities described up to this point were aiming at formulating
+assertions about a system’s behavior. If a test fails, it is usually your job
+to find the cause, fix it and verify the test again. This process is supported
+by debuggers as well as logging, where the Akka toolkit offers the following
+options:
+
+* *Logging of exceptions thrown within Actor instances*
+
+  This is always on; in contrast to the other logging mechanisms, this logs at
+  ``ERROR`` level.
+
+* *Logging of message invocations on certain actors*
+
+  This is enabled by a setting in the :ref:`configuration` — namely
+  ``akka.actor.debug.receive`` — which enables the :meth:`loggable`
+  statement to be applied to an actor’s :meth:`receive` function:
+
+.. includecode:: code/docs/testkit/TestKitDocTest.java#logging-receive
+
+.
+  If the abovementioned setting is not given in the :ref:`configuration`, this method will
+  pass through the given :class:`Receive` function unmodified, meaning that
+  there is no runtime cost unless actually enabled.
+
+  The logging feature is coupled to this specific local mark-up because
+  enabling it uniformly on all actors is not usually what you need, and it
+  would lead to endless loops if it were applied to :class:`EventHandler`
+  listeners.
+
+* *Logging of special messages*
+
+  Actors handle certain special messages automatically, e.g. :obj:`Kill`,
+  :obj:`PoisonPill`, etc. Tracing of these message invocations is enabled by
+  the setting ``akka.actor.debug.autoreceive``, which enables this on all
+  actors.
+
+* *Logging of the actor lifecycle*
+
+  Actor creation, start, restart, monitor start, monitor stop and stop may be traced by
+  enabling the setting ``akka.actor.debug.lifecycle``; this, too, is enabled
+  uniformly on all actors.
+
+All these messages are logged at ``DEBUG`` level. To summarize, you can enable
+full logging of actor activities using this configuration fragment::
+
+  akka {
+    loglevel = DEBUG
+    actor {
+      debug {
+        receive = on
+        autoreceive = on
+        lifecycle = on
+      }
+    }
+  }
+
+Different Testing Frameworks
+============================
+
+Akka’s own test suite is written using `ScalaTest`_,
+which also shines through in documentation examples. However, the TestKit and
+its facilities do not depend on that framework, you can essentially use
+whichever suits your development style best.
+
+This section contains a collection of known gotchas with some other frameworks,
+which is by no means exhaustive and does not imply endorsement or special
+support.
+
+When you need it to be a trait
+------------------------------
+
+If for some reason it is a problem to inherit from :class:`TestKit` due to it
+being a concrete class instead of a trait, there’s :class:`TestKitBase`:
+
+.. includecode:: code/docs/testkit/TestKitDocTest.java
+   :include: test-kit-base
+   :exclude: put-your-test-code-here
+
+The ``implicit lazy val system`` must be declared exactly like that (you can of
+course pass arguments to the actor system factory as needed) because trait
+:class:`TestKitBase` needs the system during its construction.
+
+.. warning::
+
+  Use of the trait is discouraged because of potential issues with binary
+  backwards compatibility in the future, use at own risk.
+
+Specs2
+------
+
+Some `Specs2`_ users have contributed examples of how to work around some clashes which may arise:
+
+* Mixing TestKit into :class:`org.specs2.mutable.Specification` results in a
+  name clash involving the ``end`` method (which is a private variable in
+  TestKit and an abstract method in Specification); if mixing in TestKit first,
+  the code may compile but might then fail at runtime. The work-around—which is
+  actually beneficial also for the third point—is to apply the TestKit together
+  with :class:`org.specs2.specification.Scope`.
+* The Specification traits provide a :class:`Duration` DSL which uses partly
+  the same method names as :class:`akka.util.Duration`, resulting in ambiguous
+  implicits if ``akka.util.duration._`` is imported. There are two work-arounds:
+
+  * either use the Specification variant of Duration and supply an implicit
+    conversion to the Akka Duration. This conversion is not supplied with the
+    Akka distribution because that would mean that our JAR files would dependon
+    Specs2, which is not justified by this little feature.
+
+  * or mix :class:`org.specs2.time.NoTimeConversions` into the Specification.
+
+* Specifications are by default executed concurrently, which requires some care
+  when writing the tests or alternatively the ``sequential`` keyword.
+
+You can use the following two examples as guidelines:
+
+.. includecode:: code/docs/testkit/Specs2DemoSpec.scala
+
+.. includecode:: code/docs/testkit/Specs2DemoAcceptance.scala
+
+
+

akka-docs/scala/code/docs/testkit/TestkitDocSpec.scala

@@ -125,7 +125,10 @@ class TestkitDocSpec extends AkkaSpec with DefaultTimeout with ImplicitSender {
 
     val actorRef = TestActorRef(new MyActor)
     // hypothetical message stimulating a '42' answer
-    val result = Await.result((actorRef ? Say42), 5 seconds).asInstanceOf[Int]
+    val future = actorRef ? Say42
+    val result = future.value.get match {
+      case Right(x: Int) ⇒ x
+    }
     result must be(42)
     //#test-behavior
   }
@@ -146,7 +149,7 @@ class TestkitDocSpec extends AkkaSpec with DefaultTimeout with ImplicitSender {
 
     val actorRef = TestActorRef(new Actor {
       def receive = {
-        case boom ⇒ throw new IllegalArgumentException("boom")
+        case "hello" ⇒ throw new IllegalArgumentException("boom")
       }
     })
     intercept[IllegalArgumentException] { actorRef.receive("hello") }

akka-docs/scala/testing.rst

@@ -67,15 +67,6 @@ Since :class:`TestActorRef` is generic in the actor type it returns the
 underlying actor with its proper static type. From this point on you may bring
 any unit testing tool to bear on your actor as usual.
 
-Expecting Exceptions
---------------------
-
-Testing that an expected exception is thrown while processing a message sent to
-the actor under test can be done by using a :class:`TestActorRef` :meth:`receive` based
-invocation:
-
-.. includecode:: code/docs/testkit/TestkitDocSpec.scala#test-expecting-exceptions
-
 .. _TestFSMRef:
 
 Testing Finite State Machines
@@ -111,8 +102,8 @@ operation to complement the :class:`Actor` testing: it supports all operations
 also valid on normal :class:`ActorRef`. Messages sent to the actor are
 processed synchronously on the current thread and answers may be sent back as
 usual. This trick is made possible by the :class:`CallingThreadDispatcher`
-described below; this dispatcher is set implicitly for any actor instantiated
+described below (see `CallingThreadDispatcher`_); this dispatcher is set
-into a :class:`TestActorRef`.
+implicitly for any actor instantiated into a :class:`TestActorRef`.
 
 .. includecode:: code/docs/testkit/TestkitDocSpec.scala#test-behavior
 
@@ -134,8 +125,8 @@ One more special aspect which is overridden for single-threaded tests is the
    dispatcher to :obj:`CallingThreadDispatcher.global` and it sets the
    :obj:`receiveTimeout` to None.
 
-The Way In-Between
+The Way In-Between: Expecting Exceptions
-------------------
+----------------------------------------
 
 If you want to test the actor behavior, including hotswapping, but without
 involving a dispatcher and without having the :class:`TestActorRef` swallow
@@ -143,10 +134,7 @@ any thrown exceptions, then there is another mode available for you: just use
 the :meth:`receive` method :class:`TestActorRef`, which will be forwarded to the
 underlying actor:
 
-.. includecode:: code/docs/testkit/TestkitDocSpec.scala#test-unhandled
+.. includecode:: code/docs/testkit/TestkitDocSpec.scala#test-expecting-exceptions
-
-The above sample assumes the default behavior for unhandled messages, i.e.
-that the actor doesn't swallow all messages and doesn't override :meth:`unhandled`.
 
 Use Cases
 ---------
@@ -205,12 +193,12 @@ Built-In Assertions
 The above mentioned :meth:`expectMsg` is not the only method for formulating
 assertions concerning received messages. Here is the full list:
 
-  * :meth:`expectMsg[T](d: Duration, msg: T): T`
+  * :meth:`expectMsg[T](d: Duration, msg: T): T`
 
     The given message object must be received within the specified time; the
     object will be returned.
 
-  * :meth:`expectMsgPF[T](d: Duration)(pf: PartialFunction[Any, T]): T`
+  * :meth:`expectMsgPF[T](d: Duration)(pf: PartialFunction[Any, T]): T`
 
     Within the given time period, a message must be received and the given
     partial function must be defined for that message; the result from applying
@@ -219,40 +207,40 @@ assertions concerning received messages. Here is the full list:
     the deadline from the innermost enclosing :ref:`within <TestKit.within>`
     block instead.
 
-  * :meth:`expectMsgClass[T](d: Duration, c: Class[T]): T`
+  * :meth:`expectMsgClass[T](d: Duration, c: Class[T]): T`
 
     An object which is an instance of the given :class:`Class` must be received
     within the allotted time frame; the object will be returned. Note that this
     does a conformance check; if you need the class to be equal, have a look at
     :meth:`expectMsgAllClassOf` with a single given class argument.
 
-  * :meth:`expectMsgType[T: Manifest](d: Duration)`
+  * :meth:`expectMsgType[T: Manifest](d: Duration)`
 
     An object which is an instance of the given type (after erasure) must be
     received within the allotted time frame; the object will be returned. This
     method is approximately equivalent to
     ``expectMsgClass(manifest[T].erasure)``.
 
-  * :meth:`expectMsgAnyOf[T](d: Duration, obj: T*): T`
+  * :meth:`expectMsgAnyOf[T](d: Duration, obj: T*): T`
 
     An object must be received within the given time, and it must be equal (
     compared with ``==``) to at least one of the passed reference objects; the
     received object will be returned.
 
-  * :meth:`expectMsgAnyClassOf[T](d: Duration, obj: Class[_ <: T]*): T`
+  * :meth:`expectMsgAnyClassOf[T](d: Duration, obj: Class[_ <: T]*): T`
 
     An object must be received within the given time, and it must be an
     instance of at least one of the supplied :class:`Class` objects; the
     received object will be returned.
 
-  * :meth:`expectMsgAllOf[T](d: Duration, obj: T*): Seq[T]`
+  * :meth:`expectMsgAllOf[T](d: Duration, obj: T*): Seq[T]`
 
     A number of objects matching the size of the supplied object array must be
     received within the given time, and for each of the given objects there
     must exist at least one among the received ones which equals (compared with
     ``==``) it. The full sequence of received objects is returned.
 
-  * :meth:`expectMsgAllClassOf[T](d: Duration, c: Class[_ <: T]*): Seq[T]`
+  * :meth:`expectMsgAllClassOf[T](d: Duration, c: Class[_ <: T]*): Seq[T]`
 
     A number of objects matching the size of the supplied :class:`Class` array
     must be received within the given time, and for each of the given classes
@@ -260,25 +248,25 @@ assertions concerning received messages. Here is the full list:
     (compared with ``==``) it (this is *not* a conformance check). The full
     sequence of received objects is returned.
 
-  * :meth:`expectMsgAllConformingOf[T](d: Duration, c: Class[_ <: T]*): Seq[T]`
+  * :meth:`expectMsgAllConformingOf[T](d: Duration, c: Class[_ <: T]*): Seq[T]`
 
     A number of objects matching the size of the supplied :class:`Class` array
     must be received within the given time, and for each of the given classes
     there must exist at least one among the received objects which is an
     instance of this class. The full sequence of received objects is returned.
 
-  * :meth:`expectNoMsg(d: Duration)`
+  * :meth:`expectNoMsg(d: Duration)`
 
     No message must be received within the given time. This also fails if a
     message has been received before calling this method which has not been
     removed from the queue using one of the other methods.
 
-  * :meth:`receiveN(n: Int, d: Duration): Seq[AnyRef]`
+  * :meth:`receiveN(n: Int, d: Duration): Seq[AnyRef]`
 
     ``n`` messages must be received within the given time; the received
     messages are returned.
 
-  * :meth:`fishForMessage(max: Duration, hint: String)(pf: PartialFunction[Any, Boolean]): Any`
+  * :meth:`fishForMessage(max: Duration, hint: String)(pf: PartialFunction[Any, Boolean]): Any`
 
     Keep receiving messages as long as the time is not used up and the partial
     function matches and returns ``false``. Returns the message received for
@@ -288,13 +276,13 @@ assertions concerning received messages. Here is the full list:
 In addition to message reception assertions there are also methods which help
 with message flows:
 
-  * :meth:`receiveOne(d: Duration): AnyRef`
+  * :meth:`receiveOne(d: Duration): AnyRef`
 
     Tries to receive one message for at most the given time interval and
     returns ``null`` in case of failure. If the given Duration is zero, the
     call is non-blocking (polling mode).
 
-  * :meth:`receiveWhile[T](max: Duration, idle: Duration, messages: Int)(pf: PartialFunction[Any, T]): Seq[T]`
+  * :meth:`receiveWhile[T](max: Duration, idle: Duration, messages: Int)(pf: PartialFunction[Any, T]): Seq[T]`
 
     Collect messages as long as
 
@@ -309,14 +297,14 @@ with message flows:
     idle timeout feature). The number of expected messages defaults to
     ``Int.MaxValue``, which effectively disables this limit.
 
-  * :meth:`awaitCond(p: => Boolean, max: Duration, interval: Duration)`
+  * :meth:`awaitCond(p: => Boolean, max: Duration, interval: Duration)`
 
     Poll the given condition every :obj:`interval` until it returns ``true`` or
     the :obj:`max` duration is used up. The interval defaults to 100 ms and the
     maximum defaults to the time remaining in the innermost enclosing
     :ref:`within <TestKit.within>` block.
 
-  * :meth:`ignoreMsg(pf: PartialFunction[AnyRef, Boolean])`
+  * :meth:`ignoreMsg(pf: PartialFunction[AnyRef, Boolean])`
 
     :meth:`ignoreNoMsg`
 

akka-testkit/src/main/scala/akka/testkit/TestActorRef.scala

@@ -132,4 +132,9 @@ object TestActorRef {
           "\nOR try to change: 'actorOf(Props[MyActor]' to 'actorOf(Props(new MyActor)'.", exception)
     }
   }), name)
+
+  /**
+   * Java API
+   */
+  def create(props: Props, name: String, system: ActorSystem) = apply(props, name)(system)
 }

akka-testkit/src/main/scala/akka/testkit/TestKit.scala

@@ -13,6 +13,7 @@ import scala.annotation.tailrec
 import akka.actor.ActorSystem
 import akka.util.Timeout
 import akka.util.BoxedType
+import scala.annotation.varargs
 
 object TestActor {
   type Ignore = Option[PartialFunction[AnyRef, Boolean]]
@@ -241,6 +242,22 @@ trait TestKitBase {
    */
   def within[T](max: Duration)(f: ⇒ T): T = within(0 seconds, max)(f)
 
+  /**
+   * Java API for within():
+   *
+   * {{{
+   * new Within(Duration.parse("3 seconds")) {
+   *   public void run() {
+   *     // your test code here
+   *   }
+   * }
+   * }}}
+   */
+  abstract class Within(max: Duration) {
+    def run(): Unit
+    within(max)(run())
+  }
+
   /**
    * Same as `expectMsg(remaining, obj)`, but correctly treating the timeFactor.
    */

project/AkkaBuild.scala

@@ -285,7 +285,8 @@ object AkkaBuild extends Build {
     settings = defaultSettings ++ Sphinx.settings ++ Seq(
       unmanagedSourceDirectories in Test <<= baseDirectory { _ ** "code" get },
       libraryDependencies ++= Dependencies.docs,
-      unmanagedSourceDirectories in ScalariformKeys.format in Test <<= unmanagedSourceDirectories in Test
+      unmanagedSourceDirectories in ScalariformKeys.format in Test <<= unmanagedSourceDirectories in Test,
+      testOptions += Tests.Argument(TestFrameworks.JUnit, "-v")
     )
   )
 
@@ -473,7 +474,7 @@ object Dependencies {
 
   val tutorials = Seq(Test.scalatest, Test.junit)
 
-  val docs = Seq(Test.scalatest, Test.junit, Test.specs2)
+  val docs = Seq(Test.scalatest, Test.junit, Test.specs2, Test.junitIntf)
 
   val zeroMQ = Seq(protobuf, Dependency.zeroMQ, Test.scalatest, Test.junit)
 }
@@ -514,6 +515,7 @@ object Dependency {
     val scalatest   = "org.scalatest"               % "scalatest_2.9.1"     % V.Scalatest  % "test" // ApacheV2
     val scalacheck  = "org.scala-tools.testing"     % "scalacheck_2.9.1"    % "1.9"        % "test" // New BSD
     val specs2      = "org.specs2"                  % "specs2_2.9.1"        % "1.9"        % "test" // Modified BSD / ApacheV2
+    val junitIntf   = "com.novocode"                % "junit-interface"     % "0.8"        % "test"
   }
 }