Passivate for Typed Sharding, #24478

* also moved singleton doc sample to own file
* and mv /doc/ to /docs/ as in other places

akka-cluster-typed/src/test/java/jdocs/akka/cluster/typed/SingletonCompileOnlyTest.java

@@ -0,0 +1,69 @@
+/**
+ * Copyright (C) 2018 Lightbend Inc. <https://www.lightbend.com>
+ */
+
+package jdocs.akka.cluster.typed;
+
+import akka.actor.typed.ActorRef;
+import akka.actor.typed.ActorSystem;
+import akka.actor.typed.Behavior;
+import akka.actor.typed.Props;
+import akka.actor.typed.javadsl.Behaviors;
+
+//#import
+import akka.cluster.typed.ClusterSingleton;
+import akka.cluster.typed.ClusterSingletonSettings;
+
+//#import
+
+public class SingletonCompileOnlyTest {
+
+  //#counter
+  interface CounterCommand {}
+  public static class Increment implements CounterCommand { }
+  public static class GoodByeCounter implements CounterCommand { }
+
+  public static class GetValue implements CounterCommand {
+    private final ActorRef<Integer> replyTo;
+    public GetValue(ActorRef<Integer> replyTo) {
+      this.replyTo = replyTo;
+    }
+  }
+
+  public static Behavior<CounterCommand> counter(String entityId, Integer value) {
+    return Behaviors.receive(CounterCommand.class)
+      .onMessage(Increment.class, (ctx, msg) -> {
+        return counter(entityId,value + 1);
+      })
+      .onMessage(GetValue.class, (ctx, msg) -> {
+        msg.replyTo.tell(value);
+        return Behaviors.same();
+      })
+      .onMessage(GoodByeCounter.class, (ctx, msg) -> {
+        return Behaviors.stopped();
+      })
+      .build();
+  }
+  //#counter
+
+  public static void example() {
+
+    ActorSystem system = ActorSystem.create(
+      Behaviors.empty(), "SingletonExample"
+    );
+
+    //#singleton
+    ClusterSingleton singleton = ClusterSingleton.get(system);
+    // Start if needed and provide a proxy to a named singleton
+    ActorRef<CounterCommand> proxy = singleton.spawn(
+      counter("TheCounter", 0),
+      "GlobalCounter",
+      Props.empty(),
+      ClusterSingletonSettings.create(system),
+      new GoodByeCounter()
+    );
+
+    proxy.tell(new Increment());
+    //#singleton
+  }
+}

akka-cluster-typed/src/test/scala/docs/akka/cluster/typed/SingletonCompileOnlySpec.scala

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+/**
+ * Copyright (C) 2018 Lightbend Inc. <https://www.lightbend.com>
+ */
+
+package docs.akka.cluster.typed
+
+import akka.actor.typed.ActorRef
+import akka.actor.typed.ActorSystem
+import akka.actor.typed.Behavior
+import akka.actor.typed.Props
+import akka.actor.typed.scaladsl.Behaviors
+
+object SingletonCompileOnlySpec {
+
+  val system = ActorSystem(Behaviors.empty, "Singleton")
+
+  //#counter
+  trait CounterCommand
+  case object Increment extends CounterCommand
+  final case class GetValue(replyTo: ActorRef[Int]) extends CounterCommand
+  case object GoodByeCounter extends CounterCommand
+
+  def counter(entityId: String, value: Int): Behavior[CounterCommand] =
+    Behaviors.receiveMessage[CounterCommand] {
+      case Increment ⇒
+        counter(entityId, value + 1)
+      case GetValue(replyTo) ⇒
+        replyTo ! value
+        Behaviors.same
+      case GoodByeCounter ⇒
+        Behaviors.stopped
+    }
+  //#counter
+
+  //#singleton
+  import akka.cluster.typed.ClusterSingleton
+  import akka.cluster.typed.ClusterSingletonSettings
+
+  val singletonManager = ClusterSingleton(system)
+  // Start if needed and provide a proxy to a named singleton
+  val proxy: ActorRef[CounterCommand] = singletonManager.spawn(
+    behavior = counter("TheCounter", 0),
+    "GlobalCounter",
+    Props.empty,
+    ClusterSingletonSettings(system),
+    terminationMessage = GoodByeCounter
+  )
+
+  proxy ! Increment
+  //#singleton
+
+}