#1470 - Document Scheduler

akka-actor/src/main/scala/akka/actor/ActorSystem.scala

@@ -262,12 +262,13 @@ abstract class ActorSystem extends ActorRefFactory {
    * effort basis and hence not strictly guaranteed.
    */
   def deadLetters: ActorRef
-
+  //#scheduler
   /**
    * Light-weight scheduler for running asynchronous tasks after some deadline
    * in the future. Not terribly precise but cheap.
    */
   def scheduler: Scheduler
+  //#scheduler
 
   /**
    * Helper object for creating new dispatchers and passing in all required

akka-actor/src/main/scala/akka/actor/Scheduler.scala

@@ -13,7 +13,7 @@
 package akka.actor
 
 import akka.util.Duration
-
+//#scheduler
 /**
  * An Akka scheduler service. This one needs one special behavior: if
  * Closeable, it MUST execute all outstanding tasks upon .close() in order
@@ -28,6 +28,8 @@ trait Scheduler {
    * Schedules a message to be sent repeatedly with an initial delay and frequency.
    * E.g. if you would like a message to be sent immediately and thereafter every 500ms you would set
    * delay = Duration.Zero and frequency = Duration(500, TimeUnit.MILLISECONDS)
+   *
+   * Java & Scala API
    */
   def schedule(initialDelay: Duration, frequency: Duration, receiver: ActorRef, message: Any): Cancellable
 
@@ -35,33 +37,53 @@ trait Scheduler {
    * Schedules a function to be run repeatedly with an initial delay and a frequency.
    * E.g. if you would like the function to be run after 2 seconds and thereafter every 100ms you would set
    * delay = Duration(2, TimeUnit.SECONDS) and frequency = Duration(100, TimeUnit.MILLISECONDS)
+   *
+   * Scala API
    */
   def schedule(initialDelay: Duration, frequency: Duration)(f: ⇒ Unit): Cancellable
 
   /**
    * Schedules a Runnable to be run once with a delay, i.e. a time period that has to pass before the runnable is executed.
+   *
+   * Java & Scala API
    */
   def scheduleOnce(delay: Duration, runnable: Runnable): Cancellable
 
   /**
    * Schedules a message to be sent once with a delay, i.e. a time period that has to pass before the message is sent.
+   *
+   * Java & Scala API
    */
   def scheduleOnce(delay: Duration, receiver: ActorRef, message: Any): Cancellable
 
   /**
    * Schedules a function to be run once with a delay, i.e. a time period that has to pass before the function is run.
+   *
+   * Scala API
    */
   def scheduleOnce(delay: Duration)(f: ⇒ Unit): Cancellable
 }
+//#scheduler
 
+//#cancellable
+/**
+ * Signifies something that can be cancelled
+ * There is no strict guarantee that the implementation is thread-safe,
+ * but it should be good practice to make it so.
+ */
 trait Cancellable {
   /**
-   * Cancels the underlying scheduled task.
+   * Cancels this Cancellable
+   *
+   * Java & Scala API
    */
   def cancel(): Unit
 
   /**
-   * Checks if the underlying scheduled task has been cancelled.
+   * Returns whether this Cancellable has been cancelled
+   *
+   * Java & Scala API
    */
   def isCancelled: Boolean
 }
+//#cancellable

akka-docs/common/scheduler.rst

@@ -1,12 +1,33 @@
 Scheduler
 =========
 
-//FIXME
+Sometimes the need for making things happen in the future arises, and where do you go look then?
+Look no further than ``ActorSystem``! There you find the :meth:``scheduler`` method that returns an instance
+of akka.actor.Scheduler, this instance is unique per ActorSystem and is used internally for scheduling things
+to happen at specific points in time. Please note that the scheduled tasks are executed by the default
+``MessageDispatcher`` of the ``ActorSystem``.
 
-Here is an example:
--------------------
+From ``akka.actor.ActorSystem``
+-------------------------------
 
-.. code-block:: scala
+.. includecode:: ../../akka-actor/src/main/scala/akka/actor/ActorSystem.scala
+   :include: scheduler
 
-  //TODO FIXME
+
+The Scheduler interface
+-----------------------
+
+.. includecode:: ../../akka-actor/src/main/scala/akka/actor/Scheduler.scala
+   :include: scheduler
+
+The Cancellable interface
+-------------------------
+
+This allows you to ``cancel`` something that has been scheduled for execution.
+
+.. warning::
+  This does not abort the execution of the task, if it had already been started.
+
+.. includecode:: ../../akka-actor/src/main/scala/akka/actor/Scheduler.scala
+   :include: cancellable