move code to src/test

* so that it compiles and tests pass
* fix some additional snip references in getting started

akka-docs/src/test/java/jdocs/pattern/SupervisedAskSpec.java

@@ -0,0 +1,30 @@
+package jdocs.pattern;
+
+import akka.actor.ActorRef;
+import akka.actor.ActorRefFactory;
+import akka.actor.Props;
+import akka.actor.AbstractActor;
+import akka.util.Timeout;
+import scala.concurrent.duration.FiniteDuration;
+
+import java.util.concurrent.CompletionStage;
+
+public class SupervisedAskSpec {
+
+  public Object execute(Class<? extends AbstractActor> someActor,
+      Object message, Timeout timeout, ActorRefFactory actorSystem)
+      throws Exception {
+    // example usage
+    try {
+      ActorRef supervisorCreator = SupervisedAsk
+          .createSupervisorCreator(actorSystem);
+      CompletionStage<Object> finished = SupervisedAsk.askOf(supervisorCreator,
+          Props.create(someActor), message, timeout);
+      FiniteDuration d = timeout.duration();
+      return finished.toCompletableFuture().get(d.length(), d.unit());
+    } catch (Exception e) {
+      // exception propagated by supervision
+      throw e;
+    }
+  }
+}