*
 * @author Jared Levy
 * @author Louis Wasserman
 */
@GwtCompatible
@SuppressWarnings("WrongCommentType") // false positive
abstract class AbstractMapBasedMultimap<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractMultimap<K, V> implements Serializable {
  /*
   * Here's an outline of the overall design.
   *
   * The map variable contains the collection of values associated with each

   */
  @IgnoreJRERequirement // Users will use this only if they're already using streams.
  public static <T extends @Nullable Object, K extends Comparable<? super K>, V>
      Collector<T, ?, ImmutableRangeMap<K, V>> toImmutableRangeMap(
          Function<? super T, Range<K>> keyFunction,
          Function<? super T, ? extends V> valueFunction) {
    return CollectCollectors.toImmutableRangeMap(keyFunction, valueFunction);
  }

  /**

  private static class NoOpThreadedService extends AbstractExecutionThreadService {
    final CountDownLatch latch = new CountDownLatch(1);

    @Override
    protected void run() throws Exception {
      latch.await();
    }

    @Override
    protected void triggerShutdown() {
      latch.countDown();
    }
  }

  private static class StartFailingService extends AbstractService {
    @Override

  private static class NoOpThreadedService extends AbstractExecutionThreadService {
    final CountDownLatch latch = new CountDownLatch(1);

    @Override
    protected void run() throws Exception {
      latch.await();
    }

    @Override
    protected void triggerShutdown() {
      latch.countDown();
    }
  }

  private static class StartFailingService extends AbstractService {
    @Override

        }

        @Override
        public <T extends java.util.EventListener> void addListener(T t) {
        }

        @Override
        public void addListener(Class<? extends java.util.EventListener> listenerClass) {
        }

        @Override
        public <T extends java.util.EventListener> T createListener(Class<T> clazz) {
            return null;
        }

        Class<?> clazz = info.load();
        // TODO(cpovirk): why does asSubclass() throw? Is it something about ClassLoaders?
        @SuppressWarnings("unchecked")
        Class<? extends GWTTestCase> cast = (Class<? extends GWTTestCase>) clazz;
        suite.addTestSuite(cast);
      }
    }
    return suite;
  }

   *
   * @since 11.0 (generics widened in 13.0)
   */
  public static <T> Iterable<T> presentInstances(
      Iterable<? extends Optional<? extends T>> optionals) {
    checkNotNull(optionals);
    return () ->
        new AbstractIterator<T>() {
          private final Iterator<? extends Optional<? extends T>> iterator =
              checkNotNull(optionals.iterator());

          @Override

  }

  @Override
  public <S extends Comparable<?>> Ordering<S> reverse() {
    return Ordering.natural();
  }

  // Override the min/max methods to "hoist" delegation outside loops

  @Override
  public <E extends Comparable<?>> E min(E a, E b) {
    return NaturalOrdering.INSTANCE.max(a, b);
  }

  @Override
  public <E extends Comparable<?>> E min(E a, E b, E c, E... rest) {

      Iterable<? extends Entry<? extends K, ? extends V>> entries) {
    return new Builder<K, V>().putAll(entries).build();
  }

  /** Creates an ImmutableListMultimap from an asMap.entrySet. */
  static <K, V> ImmutableListMultimap<K, V> fromMapEntries(
      Collection<? extends Map.Entry<? extends K, ? extends Collection<? extends V>>> mapEntries,

    @Override
    public void acceptPrimaryKeyMap(Entity entity, Map<String, ? extends Object> primaryKeyMap) {
    }

    @Override
    public void acceptAllColumnMap(Entity entity, Map<String, ? extends Object> allColumnMap) {
    }

    @Override
    public Map<String, Object> extractPrimaryKeyMap(Entity entity) {
        return null;
    }