#22903 Fix code snippeds

* move scala and java sources out of paradox sources
* replace relative paths with $code$ and $akka$
* fix broken includes

akka-docs/src/main/java/jdocs/actor/InboxDocTest.java

@@ -0,0 +1,66 @@
+/**
+ * Copyright (C) 2009-2017 Lightbend Inc. <http://www.lightbend.com>
+ */
+
+package jdocs.actor;
+
+import java.util.concurrent.TimeUnit;
+
+import akka.testkit.AkkaJUnitActorSystemResource;
+import jdocs.AbstractJavaTest;
+import akka.testkit.javadsl.TestKit;
+import org.junit.ClassRule;
+import org.junit.Test;
+
+import scala.concurrent.duration.Duration;
+import akka.actor.ActorRef;
+import akka.actor.ActorSystem;
+import akka.actor.Inbox;
+import akka.actor.PoisonPill;
+import akka.actor.Terminated;
+import akka.testkit.AkkaSpec;
+
+public class InboxDocTest extends AbstractJavaTest {
+
+  @ClassRule
+  public static AkkaJUnitActorSystemResource actorSystemResource =
+    new AkkaJUnitActorSystemResource("InboxDocTest", AkkaSpec.testConf());
+
+  private final ActorSystem system = actorSystemResource.getSystem();
+
+  @Test
+  public void demonstrateInbox() {
+    final TestKit probe = new TestKit(system);
+    final ActorRef target = probe.getRef();
+    //#inbox
+    final Inbox inbox = Inbox.create(system);
+    inbox.send(target, "hello");
+    //#inbox
+    probe.expectMsgEquals("hello");
+    probe.send(probe.getLastSender(), "world");
+    //#inbox
+    try {
+      assert inbox.receive(Duration.create(1, TimeUnit.SECONDS)).equals("world");
+    } catch (java.util.concurrent.TimeoutException e) {
+      // timeout
+    }
+    //#inbox
+  }
+  
+  @Test
+  public void demonstrateWatch() {
+    final TestKit probe = new TestKit(system);
+    final ActorRef target = probe.getRef();
+    //#watch
+    final Inbox inbox = Inbox.create(system);
+    inbox.watch(target);
+    target.tell(PoisonPill.getInstance(), ActorRef.noSender());
+    try {
+      assert inbox.receive(Duration.create(1, TimeUnit.SECONDS)) instanceof Terminated;
+    } catch (java.util.concurrent.TimeoutException e) {
+      // timeout
+    }
+    //#watch
+  }
+
+}