Added patterns for initialization for Scala #2297

(cherry-picked from e2aa3b5)

akka-docs/rst/java/code/docs/actor/InitializationDocSpecJava.java

@@ -0,0 +1,95 @@
+package docs.actor;
+
+import akka.actor.*;
+import akka.japi.Procedure;
+import akka.testkit.JavaTestKit;
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
+import org.junit.Test;
+import scala.Option;
+
+/**
+ * Copyright (C) 2009-2013 Typesafe Inc. <http://www.typesafe.com>
+ */
+public class InitializationDocSpecJava {
+
+    static public class PreStartInitExample extends UntypedActor {
+
+        public void onReceive(Object message) throws Exception {}
+
+        //#preStartInit
+        @Override
+        public void preStart() {
+            // Initialize children here
+        }
+
+        // Overriding postRestart to disable the call to preStart()
+        // after restarts
+        @Override
+        public void postRestart(Throwable reason) {
+        }
+
+        // The default implementation of preRestart() stops all the children
+        // of the actor. To opt-out from stopping the children, we
+        // have to override preRestart()
+        @Override
+        public void preRestart(Throwable reason, Option<Object> message) {
+            // Keep the call to postStop(), but no stopping of children
+            postStop();
+        }
+        //#preStartInit
+
+    }
+
+    public static class MessageInitExample extends UntypedActor {
+        //#messageInit
+        private String initializeMe = null;
+
+        @Override
+        public void onReceive(Object message) throws Exception {
+            if (message.equals("init")) {
+                initializeMe = "Up and running";
+                getContext().become(new Procedure<Object>() {
+                    @Override
+                    public void apply(Object message) throws Exception {
+                        if (message.equals("U OK?"))
+                        getSender().tell(initializeMe, getSelf());
+                    }
+                });
+            }
+        }
+        //#messageInit
+    }
+
+    static ActorSystem system;
+
+    @BeforeClass
+    public static void setup() {
+        system = ActorSystem.create("TestSystem");
+    }
+
+    @AfterClass
+    public static void teardown() {
+        system.shutdown();
+    }
+
+    @Test
+    public void testIt() {
+
+        new JavaTestKit(system) {{
+            ActorRef testactor = system.actorOf(new Props(MessageInitExample.class), "testactor");
+            String probe = "U OK?";
+
+            testactor.tell(probe, getRef());
+            expectNoMsg();
+
+            testactor.tell("init", getRef());
+            testactor.tell(probe, getRef());
+            expectMsgEquals("Up and running");
+        }};
+
+
+
+    }
+
+}