private void assertAnnouncement(
     Set<ServiceAnnouncement> actualAnnouncements, ServiceAnnouncement expected) {
   Assert.assertNotNull(actualAnnouncements);
   Assert.assertEquals(actualAnnouncements.size(), 1);
   ServiceAnnouncement announcement = Iterables.getOnlyElement(actualAnnouncements);
   Assert.assertEquals(announcement.getType(), expected.getType());
   Assert.assertEquals(announcement.getProperties(), expected.getProperties());
 }