} else if (obj instanceof Failure) {
      throw new ExecutionException(((Failure) obj).exception);
    } else if (obj == NULL) {
      /*
       * It's safe to return null because we would only have stored it in the first place if it were
       * a valid value for V.
       */
      return uncheckedNull();
    } else {

  }

  private ImmutableSortedMap<K, V> getSubMap(int fromIndex, int toIndex) {
    if (fromIndex == 0 && toIndex == size()) {
      return this;
    } else if (fromIndex == toIndex) {
      return emptyMap(comparator());
    } else {
      return new ImmutableSortedMap<>(
          keySet.getSubSet(fromIndex, toIndex), valueList.subList(fromIndex, toIndex));
    }
  }

  /**

  private static String badElementIndex(int index, int size, String desc) {
    if (index < 0) {
      return lenientFormat("%s (%s) must not be negative", desc, index);
    } else if (size < 0) {
      throw new IllegalArgumentException("negative size: " + size);
    } else { // index >= size
      return lenientFormat("%s (%s) must be less than size (%s)", desc, index, size);
    }
  }

  /**

                  try {
                    int mod = index % 3;
                    if (mod == 0) {
                      value = cache.get(key);
                    } else if (mod == 1) {
                      value = cache.getUnchecked(key);
                    } else {
                      cache.refresh(key);
                      value = cache.get(key);
                    }
                    result.set(index, value);

      return this.someRawTypeIsSubclassOf((Class<?>) supertype);
    } else if (supertype instanceof ParameterizedType) {
      return this.isSubtypeOfParameterizedType((ParameterizedType) supertype);
    } else if (supertype instanceof GenericArrayType) {
      return this.isSubtypeOfArrayType((GenericArrayType) supertype);
    } else { // to instanceof TypeVariable
      return false;
    }
  }

  /**

      } else if (collection instanceof SortedSet) {
        return Collections.unmodifiableSortedSet((SortedSet<E>) collection);
      } else if (collection instanceof Set) {
        return Collections.unmodifiableSet((Set<E>) collection);
      } else if (collection instanceof List) {
        return Collections.unmodifiableList((List<E>) collection);
      } else {

  }

  private ImmutableSortedMap<K, V> getSubMap(int fromIndex, int toIndex) {
    if (fromIndex == 0 && toIndex == size()) {
      return this;
    } else if (fromIndex == toIndex) {
      return emptyMap(comparator());
    } else {
      return new ImmutableSortedMap<>(
          keySet.getSubSet(fromIndex, toIndex), valueList.subList(fromIndex, toIndex));
    }
  }

  /**

              this.count = newCount; // write-volatile
              return null;
            } else if (onlyIfAbsent) {
              // Mimic
              // "if (!map.containsKey(key)) ...
              // else return map.get(key);
              return entryValue;
            } else {
              // clobber existing entry, count remains unchanged
              ++modCount;

      return (ImmutableEnumSet<E>) elements;
    } else if (elements instanceof Collection) {
      Collection<E> collection = (Collection<E>) elements;
      if (collection.isEmpty()) {
        return ImmutableSet.of();
      } else {
        return ImmutableEnumSet.asImmutable(EnumSet.copyOf(collection));
      }
    } else {
      Iterator<E> itr = elements.iterator();
      if (itr.hasNext()) {

   */
  private static <E> void verifySetContents(Set<E> set, Iterable<E> contents) {
    Set<E> expected = null;
    if (contents instanceof Set) {
      expected = (Set<E>) contents;
    } else {
      expected = new HashSet<E>();
      for (E element : contents) {
        expected.add(element);
      }
    }
    assertEquals(expected, set);
  }

  @GwtIncompatible // NavigableSet