private final IntegerSubscriber i2 = new IntegerSubscriber("i2");
  private final IntegerSubscriber i3 = new IntegerSubscriber("i3");
  private final ImmutableList<Subscriber> integerSubscribers =
      ImmutableList.of(
          subscriber(bus, i1, "handleInteger", Integer.class),
          subscriber(bus, i2, "handleInteger", Integer.class),

  private final IntegerSubscriber i2 = new IntegerSubscriber("i2");
  private final IntegerSubscriber i3 = new IntegerSubscriber("i3");
  private final ImmutableList<Subscriber> integerSubscribers =
      ImmutableList.of(
          subscriber(bus, i1, "handleInteger", Integer.class),
          subscriber(bus, i2, "handleInteger", Integer.class),

    List<String> list = Lists.newArrayList("a", "b");

    // Test & Verify
    Iterator<String> i1 = Iterators.consumingIterator(list.iterator());
    Iterator<String> i2 = Iterators.consumingIterator(list.iterator());

    i1.next();
    try {
      i2.next();
      fail("Concurrent modification should throw an exception.");
    } catch (ConcurrentModificationException cme) {
      // Pass
    }
  }

    // Test & Verify
    Iterator<String> i1 = Iterables.consumingIterable(list).iterator();
    Iterator<String> i2 = Iterables.consumingIterable(list).iterator();

    i1.next();
    try {
      i2.next();
      fail("Concurrent modification should throw an exception.");
    } catch (ConcurrentModificationException cme) {
      // Pass
    }
  }

    // Test & Verify
    Iterator<String> i1 = Iterables.consumingIterable(list).iterator();
    Iterator<String> i2 = Iterables.consumingIterable(list).iterator();

    i1.next();
    try {
      i2.next();
      fail("Concurrent modification should throw an exception.");
    } catch (ConcurrentModificationException cme) {
      // Pass
    }
  }

    List<String> list = Lists.newArrayList("a", "b");

    // Test & Verify
    Iterator<String> i1 = Iterators.consumingIterator(list.iterator());
    Iterator<String> i2 = Iterators.consumingIterator(list.iterator());

    i1.next();
    try {
      i2.next();
      fail("Concurrent modification should throw an exception.");
    } catch (ConcurrentModificationException cme) {
      // Pass
    }
  }