public Builder<E> add(E... elements) {
      for (E element : elements) {
        add(element);
      }
      return this;
    }

    /**
     * Adds each element of {@code elements} to the {@code ImmutableCollection} being built.
     *
     * <p>Note that each builder class overrides this method in order to covariantly return its own
     * type.
     *
     * @param elements the elements to add

     * elements (only the first duplicate element is added).
     *
     * @param elements the elements to add
     * @return this {@code Builder} object
     * @throws NullPointerException if {@code elements} is null or contains a null element
     */
    @Override
    @CanIgnoreReturnValue
    public Builder<E> addAll(Iterable<? extends E> elements) {

    // We special-case for 0 or 1 elements, but going further is madness.
    if (!elements.hasNext()) {
      return of();
    }
    E first = elements.next();
    if (!elements.hasNext()) {
      return of(first);
    } else {
      return new ImmutableList.Builder<E>().add(first).addAll(elements).build();
    }
  }

  /**
   * Returns an immutable list containing the given elements, in order.

    }

    @Override
    public SampleElements<E> samples() {
      return gen.samples();
    }

    @Override
    public Set<E> create(Object... elements) {
      return (Set<E>) SerializableTester.reserialize(gen.create(elements));
    }

    @Override
    public E[] createArray(int length) {
      return gen.createArray(length);
    }

    @Override

    int index = headIndex(element, true) - 1;
    return (index == -1) ? null : elements.get(index);
  }

  @Override
  public @Nullable E ceiling(E element) {
    int index = tailIndex(element, true);
    return (index == size()) ? null : elements.get(index);
  }

  @Override
  public @Nullable E higher(E element) {
    int index = tailIndex(element, false);

    E[] elements = createSamplesArray();
    E duplicate = elements[(elements.length / 2) - 1];
    elements[(elements.length / 2) + 1] = duplicate;
    return new ArrayWithDuplicate<>(elements, duplicate);
  }

  // Helper methods to improve readability of derived classes

  protected int getNumElements() {
    return getSubjectGenerator().getCollectionSize().getNumElements();
  }

   * have been removed.
   *
   * <p><b>Warning:</b> Typical uses of the resulting iterator may produce an infinite loop. You
   * should use an explicit {@code break} or be certain that you will eventually remove all the
   * elements.
   *
   * <p>To cycle over the elements {@code n} times, use the following: {@code
   * Iterables.concat(Collections.nCopies(n, Arrays.asList(elements)))}
   *

  @JsMethod(name = "of")
  static <E> ImmutableList<E> jsOf(E... elements) {
    return copyOf(elements);
  }

  public static <E> ImmutableList<E> copyOf(Iterable<? extends E> elements) {
    checkNotNull(elements); // for GWT
    return (elements instanceof Collection)
        ? copyOf((Collection<? extends E>) elements)
        : copyOf(elements.iterator());
  }

  // also mean that the iterator returns the head element first, which those
  // don't.

  public Test testsForPriorityBlockingQueue() {
    return QueueTestSuiteBuilder.using(
            new TestStringQueueGenerator() {
              @Override
              public Queue<String> create(String[] elements) {
                return new PriorityBlockingQueue<>(MinimalCollection.of(elements));
              }
            })

    @Override
    protected List<Short> create(Short[] elements) {
      return asList(elements);
    }
  }

  public static final class ShortsAsListHeadSubListGenerator extends TestShortListGenerator {
    @Override
    protected List<Short> create(Short[] elements) {
      Short[] suffix = {Short.MIN_VALUE, Short.MAX_VALUE};
      Short[] all = concat(elements, suffix);
      return asList(all).subList(0, elements.length);