From a8080a214040c060cff1e62c016ae19b20feb45c Mon Sep 17 00:00:00 2001
From: Nicolas Vollmar <nvo@scaling.ch>
Date: Fri, 21 Dec 2018 19:06:30 +0100
Subject: [PATCH] Improving documentation and code style #26156

---
 .../akka/pattern/BackoffOnStopSupervisor.scala      |  9 +++------
 .../main/scala/akka/pattern/BackoffOptions.scala    |  5 +++--
 .../main/scala/akka/pattern/BackoffSupervisor.scala |  2 +-
 .../src/main/scala/akka/pattern/HandleBackoff.scala | 13 +++++++------
 4 files changed, 14 insertions(+), 15 deletions(-)

diff --git a/akka-actor/src/main/scala/akka/pattern/BackoffOnStopSupervisor.scala b/akka-actor/src/main/scala/akka/pattern/BackoffOnStopSupervisor.scala
index a2526fb8d4..89073e6f6f 100644
--- a/akka-actor/src/main/scala/akka/pattern/BackoffOnStopSupervisor.scala
+++ b/akka-actor/src/main/scala/akka/pattern/BackoffOnStopSupervisor.scala
@@ -78,15 +78,12 @@ private[akka] class BackoffOnStopSupervisor(
       }
     case None ⇒
       replyWhileStopped match {
-        case None    ⇒ context.system.deadLetters.forward(msg)
         case Some(r) ⇒ sender() ! r
+        case None    ⇒ context.system.deadLetters.forward(msg)
       }
       finalStopMessage match {
-        case None ⇒
-        case Some(fsm) ⇒
-          if (fsm(msg)) {
-            context.stop(self)
-          }
+        case Some(fsm) if fsm(msg) ⇒ context.stop(self)
+        case _                     ⇒
       }
   }
 }
diff --git a/akka-actor/src/main/scala/akka/pattern/BackoffOptions.scala b/akka-actor/src/main/scala/akka/pattern/BackoffOptions.scala
index a629b4eaa7..5b90e6ae63 100644
--- a/akka-actor/src/main/scala/akka/pattern/BackoffOptions.scala
+++ b/akka-actor/src/main/scala/akka/pattern/BackoffOptions.scala
@@ -552,8 +552,9 @@ trait BackoffOptions {
    * Returns a new BackoffOptions with a maximum number of retries to restart the child actor.
    * By default, the supervisor will retry infinitely.
    * With this option, the supervisor will terminate itself after the maxNoOfRetries is reached.
-   * @param maxNrOfRetries the number of times a child actor is allowed to be restarted, negative value means no limit,
-   *  if the limit is exceeded the child actor is stopped
+   * @param maxNrOfRetries the number of times a child actor is allowed to be restarted.
+   *                       If negative, the value is unbounded, otherwise the provided
+   *                       limit is used. If the limit is exceeded the child actor will be stopped.
    */
   def withMaxNrOfRetries(maxNrOfRetries: Int): BackoffOptions
 
diff --git a/akka-actor/src/main/scala/akka/pattern/BackoffSupervisor.scala b/akka-actor/src/main/scala/akka/pattern/BackoffSupervisor.scala
index b88f012f39..0aa462a91a 100644
--- a/akka-actor/src/main/scala/akka/pattern/BackoffSupervisor.scala
+++ b/akka-actor/src/main/scala/akka/pattern/BackoffSupervisor.scala
@@ -278,7 +278,7 @@ object BackoffSupervisor {
 }
 
 // for backwards compability
-@deprecated("Use BackoffSupervisor props method instead", since = "2.5.20")
+@deprecated("Use `BackoffSupervisor.props` method instead", since = "2.5.20")
 final class BackoffSupervisor(
   override val childProps: Props,
   override val childName:  String,
diff --git a/akka-actor/src/main/scala/akka/pattern/HandleBackoff.scala b/akka-actor/src/main/scala/akka/pattern/HandleBackoff.scala
index 7920967656..4798ec75a5 100644
--- a/akka-actor/src/main/scala/akka/pattern/HandleBackoff.scala
+++ b/akka-actor/src/main/scala/akka/pattern/HandleBackoff.scala
@@ -6,6 +6,9 @@ package akka.pattern
 
 import akka.actor.{ Actor, ActorRef, Props }
 
+/**
+ * Implements basic backoff handling for [[BackoffOnRestartSupervisor]] and [[BackoffOnStopSupervisor]].
+ */
 private[akka] trait HandleBackoff {
   this: Actor ⇒
   def childProps: Props
@@ -22,18 +25,16 @@ private[akka] trait HandleBackoff {
 
   override def preStart(): Unit = startChild()
 
-  def startChild(): Unit = {
-    if (child.isEmpty) {
-      child = Some(context.watch(context.actorOf(childProps, childName)))
-    }
+  def startChild(): Unit = if (child.isEmpty) {
+    child = Some(context.watch(context.actorOf(childProps, childName)))
   }
 
-  def handleBackoff: Receive = {
+  def handleBackoff: Actor.Receive = {
     case StartChild ⇒
       startChild()
       reset match {
         case AutoReset(resetBackoff) ⇒
-          val _ = context.system.scheduler.scheduleOnce(resetBackoff, self, ResetRestartCount(restartCount))
+          context.system.scheduler.scheduleOnce(resetBackoff, self, ResetRestartCount(restartCount))
         case _ ⇒ // ignore
       }