@GwtCompatible(serializable = true, emulated = true)
@ElementTypesAreNonnullByDefault
class ObjectCountHashMap<K extends @Nullable Object> {

  /** Creates an empty {@code ObjectCountHashMap} instance. */
  static <K extends @Nullable Object> ObjectCountHashMap<K> create() {
    return new ObjectCountHashMap<K>();
  }

  /**
   * Creates a {@code ObjectCountHashMap} instance, with a high enough "initial capacity" that it

        return false;
      }
    }
    return true;
  }

  private static <E extends @Nullable Object> ObjectCountHashMap<E> counts(
      Collection<E> collection) {
    ObjectCountHashMap<E> map = new ObjectCountHashMap<>();
    for (E e : collection) {
      map.put(e, map.get(e) + 1);
    }
    return map;
  }