ActorSystem { public static void unregister(@NonNull Object actor) { implementation.unregister(actor); } private  ActorSystem(); static MessageBuilder createMessage(int id); static void send(int messageId, @NonNull Class<?>... actorsAddresses); static void send(final Message message, @NonNull Class<?>... actorsAddresses); static void send(int messageId, @NonNull String... actorsClassNames); static void send(final Message message, @NonNull String... actorsClassNames); @Deprecated static void register(@NonNull Object actor,
                                @NonNull final Scheduler observeOn,
                                @NonNull final Consumer<Message> onMessageReceived); static void register(@NonNull final Actor actor); @Deprecated static void register(@NonNull Object actor, @NonNull Consumer<MailboxBuilder> mailboxBuilder); static void postpone(@NonNull Object actor); static void unregister(@NonNull Object actor);  }
@Test public void unregisterNonRegisteredActorAndDoNotCrash() throws Exception { ActorSystemInstance .getInstance("unregisterNonRegisteredActorAndDoNotCrash") .unregister(TestActorFive.class); }