}
      return newCapacity;
    }

    Builder() {}

    /**
     * Adds {@code element} to the {@code ImmutableCollection} being built.
     *
     * <p>Note that each builder class covariantly returns its own type from this method.
     *
     * @param element the element to add
     * @return this {@code Builder} instance
     * @throws NullPointerException if {@code element} is null
     */

      Iterator<? extends T> iterator) {
    if (iterator instanceof PeekingImpl) {
      // Safe to cast <? extends T> to <T> because PeekingImpl only uses T
      // covariantly (and cannot be subclassed to add non-covariant uses).
      @SuppressWarnings("unchecked")
      PeekingImpl<T> peeking = (PeekingImpl<T>) iterator;
      return peeking;
    }
    return new PeekingImpl<>(iterator);
  }

  @Override
  ImmutableCollection<E> delegateCollection() {
    return delegate;
  }

  ImmutableList<? extends E> delegateList() {
    return delegateList;
  }

  @SuppressWarnings("unchecked") // safe covariant cast!
  @Override
  public UnmodifiableListIterator<E> listIterator(int index) {
    return (UnmodifiableListIterator<E>) delegateList.listIterator(index);
  }

  @GwtIncompatible // not present in emulated superclass

  @Override
  ImmutableCollection<E> delegateCollection() {
    return delegate;
  }

  ImmutableList<? extends E> delegateList() {
    return delegateList;
  }

  @SuppressWarnings("unchecked") // safe covariant cast!
  @Override
  public UnmodifiableListIterator<E> listIterator(int index) {
    return (UnmodifiableListIterator<E>) delegateList.listIterator(index);
  }

  @GwtIncompatible // not present in emulated superclass

       * TODO: When given an ImmutableList that's a sublist, copy the referenced
       * portion of the array into a new array to save space?
       */
      @SuppressWarnings("unchecked") // all supported methods are covariant
      ImmutableCollection<E> list = (ImmutableCollection<E>) elements;
      return list.asList();
    }
    return copyFromCollection(elements);
  }

  @JsMethod

    FluentIterable<? extends Number> numbers = getSomeNumbers();

    // Sadly, the following is what users will have to do in some circumstances.

    @SuppressWarnings("unchecked") // safe covariant cast
    Optional<Number> first = (Optional<Number>) numbers.first();
    Number value = first.or(0.5); // fine
  }

  @J2ktIncompatible
  @GwtIncompatible // NullPointerTester

    UnmodifiableTable(Table<? extends R, ? extends C, ? extends V> delegate) {
      this.delegate = checkNotNull(delegate);
    }

    @SuppressWarnings("unchecked") // safe, covariant cast
    @Override
    protected Table<R, C, V> delegate() {
      return (Table<R, C, V>) delegate;
    }

    @Override
    public Set<Cell<R, C, V>> cellSet() {

   */
  public static <E> ImmutableList<E> copyOf(Collection<? extends E> elements) {
    if (elements instanceof ImmutableCollection) {
      @SuppressWarnings("unchecked") // all supported methods are covariant
      ImmutableList<E> list = ((ImmutableCollection<E>) elements).asList();
      return list.isPartialView() ? ImmutableList.<E>asImmutableList(list.toArray()) : list;
    }
    return construct(elements.toArray());

      Multiset<? extends E> multiset) {
    if (multiset instanceof UnmodifiableMultiset || multiset instanceof ImmutableMultiset) {
      @SuppressWarnings("unchecked") // Since it's unmodifiable, the covariant cast is safe
      Multiset<E> result = (Multiset<E>) multiset;
      return result;
    }
    return new UnmodifiableMultiset<>(checkNotNull(multiset));
  }

  /**
   * Simply returns its argument.

      Multiset<? extends E> multiset) {
    if (multiset instanceof UnmodifiableMultiset || multiset instanceof ImmutableMultiset) {
      @SuppressWarnings("unchecked") // Since it's unmodifiable, the covariant cast is safe
      Multiset<E> result = (Multiset<E>) multiset;
      return result;
    }
    return new UnmodifiableMultiset<>(checkNotNull(multiset));
  }

  /**
   * Simply returns its argument.