bus = new AsyncEventBus(executor);
  }

  public void testBasicDistribution() {
    StringCatcher catcher = new StringCatcher();
    bus.register(catcher);

    // We post the event, but our Executor will not deliver it until instructed.
    bus.post(EVENT);

    List<String> events = catcher.getEvents();
    assertTrue("No events should be delivered synchronously.", events.isEmpty());

  @GwtIncompatible // SerializableTester
  public void testIsNull_serialization() {
    Predicate<String> pre = Predicates.isNull();
    Predicate<String> post = SerializableTester.reserializeAndAssert(pre);
    assertEquals(pre.apply("foo"), post.apply("foo"));
    assertEquals(pre.apply(null), post.apply(null));
  }

  public void testNotNull_apply() {
    Predicate<@Nullable Integer> notNull = Predicates.notNull();

  void setUp() {
    eventBus = new EventBus("for benchmarking purposes");
    eventBus.register(this);
  }

  @Benchmark
  void postStrings(int reps) {
    for (int i = 0; i < reps; i++) {
      eventBus.post("hello there");
    }
  }

  @Subscribe
  public void handleStrings(String string) {
    // Nothing to do here.
  }

    return subscriber;
  }

  @Override
  protected void setUp() throws Exception {
    subscriber = createSubscriber();
    EventBus bus = new EventBus();
    bus.register(subscriber);
    bus.post(EVENT);
  }

  @Override
  protected void tearDown() throws Exception {
    subscriber = null;
  }

    bus.register(compCatcher);

    // Two additional event types: Object and Comparable<?> (played by Integer)
    Object objEvent = new Object();
    Object compEvent = 6;

    bus.post(EVENT);
    bus.post(objEvent);
    bus.post(compEvent);

    // Check the StringCatcher...
    List<String> stringEvents = stringCatcher.getEvents();
    assertEquals("Only one String should be delivered.", 1, stringEvents.size());

    bus.register(compCatcher);

    // Two additional event types: Object and Comparable<?> (played by Integer)
    Object objEvent = new Object();
    Object compEvent = 6;

    bus.post(EVENT);
    bus.post(objEvent);
    bus.post(compEvent);

    // Check the StringCatcher...
    List<String> stringEvents = stringCatcher.getEvents();
    assertEquals("Only one String should be delivered.", 1, stringEvents.size());

      </plugin>
      <plugin>
        <artifactId>maven-source-plugin</artifactId>
        <executions>
          <execution>
            <id>attach-test-sources</id>
            <phase>post-integration-test</phase>
            <goals><goal>test-jar</goal></goals>
          </execution>
        </executions>
      </plugin>
      <plugin>
        <artifactId>maven-jar-plugin</artifactId>

    bus.register(recorder);

    bus.post(FIRST);

    assertEquals(
        "EventRecorder expected events in order",
        Lists.<Object>newArrayList(FIRST, SECOND),
        recorder.eventsReceived);
  }

  public class EventProcessor {
    @Subscribe
    public void listenForStrings(String event) {
      bus.post(SECOND);
    }
  }

  public class EventRecorder {

      </plugin>
      <plugin>
        <artifactId>maven-source-plugin</artifactId>
        <executions>
          <execution>
            <id>attach-test-sources</id>
            <phase>post-integration-test</phase>
            <goals><goal>test-jar</goal></goals>
          </execution>
        </executions>
      </plugin>
      <plugin>
        <artifactId>maven-surefire-plugin</artifactId>

  @GwtIncompatible // SerializableTester
  public void testIsNull_serialization() {
    Predicate<String> pre = Predicates.isNull();
    Predicate<String> post = SerializableTester.reserializeAndAssert(pre);
    assertEquals(pre.apply("foo"), post.apply("foo"));
    assertEquals(pre.apply(null), post.apply(null));
  }

  public void testNotNull_apply() {
    Predicate<@Nullable Integer> notNull = Predicates.notNull();