public int hashCode() {
    return Sets.hashCodeImpl(this);
  }

  // This declaration is needed to make Set.iterator() and
  // ImmutableCollection.iterator() appear consistent to javac's type inference.
  @Override
  public abstract UnmodifiableIterator<E> iterator();

  abstract static class CachingAsList<E> extends ImmutableSet<E> {
    @LazyInit private transient ImmutableList<E> asList;

    @Override

    assertNextThrows(iterator);

    /* Checks the case where a later element throws an exception. */

    list = Lists.newArrayList(1, 2);
    iterator = peekingIterator(new ThrowsAtEndIterator<Integer>(list));
    assertTrue(iterator.hasNext());
    iterator.next();
    assertTrue(iterator.hasNext());
    iterator.next();
    assertNextThrows(iterator);
  }

  private void assertNextThrows(Iterator<?> iterator) {

        @Override
        public Set<Entry<Object, Object>> entrySet() {
            return new AbstractImmutableSet<>() {
                @Override
                public Iterator<Entry<Object, Object>> iterator() {
                    return new Iterator<>() {
                        @Override
                        public boolean hasNext() {
                            return false;
                        }

    } else if (isEmpty()) {
      return true;
    }

    if (SortedIterables.hasSameComparator(comparator, that)) {
      Iterator<?> otherIterator = that.iterator();
      try {
        Iterator<E> iterator = iterator();
        while (iterator.hasNext()) {
          Object element = iterator.next();
          Object otherElement = otherIterator.next();

  public void testCopyOf_iterator_empty() {
    Iterator<String> iterator = emptyIterator();
    Set<String> set = copyOf(iterator);
    assertEquals(Collections.<String>emptySet(), set);
    assertThat(set).isSameInstanceAs(this.<String>of());
  }

  public void testCopyOf_iterator_oneElement() {
    Iterator<String> iterator = singletonIterator("a");
    Set<String> set = copyOf(iterator);
    assertEquals(singleton("a"), set);
  }

    Iterator<Integer> iter =
        new AbstractIterator<Integer>() {
          @Override
          public Integer computeNext() {
            endOfData();
            throw new SomeUncheckedException();
          }
        };
    assertThrows(SomeUncheckedException.class, iter::hasNext);
  }

  public void testCantRemove() {
    Iterator<Integer> iter =

   */
  static class IteratorWithJdkBug6529795<T> implements Iterator<T> {
    Iterator<T> iterator;
    boolean nextThrewException;

    IteratorWithJdkBug6529795(Iterator<T> iterator) {
      this.iterator = iterator;
    }

    @Override
    public boolean hasNext() {
      return iterator.hasNext();
    }

    @Override
    public T next() {
      try {

  /**
   * A sensible definition of {@link #firstEntry()} in terms of {@code entrySet().iterator()}.
   *
   * <p>If you override {@link #entrySet()}, you may wish to override {@link #firstEntry()} to
   * forward to this implementation.
   */
  protected @Nullable Entry<E> standardFirstEntry() {
    Iterator<Entry<E>> entryIterator = entrySet().iterator();
    if (!entryIterator.hasNext()) {
      return null;
    }

      return oldValue;
    }
  }

  Iterator<Entry<K, V>> entrySetIterator() {
    Iterator<Entry<K, V>> iterator = delegate.entrySet().iterator();
    return new Iterator<Entry<K, V>>() {
      @Nullable Entry<K, V> entry;

      @Override
      public boolean hasNext() {
        return iterator.hasNext();
      }

      @Override
      public Entry<K, V> next() {

        assertArgumentNotNull("iterator", iterator);

        return () -> new IndexedIterator<>(iterator);
    }

    /**
     * Constructs an instance.
     *
     * @param iterator the iterator (must not be {@literal null})
     */
    public IndexedIterator(final Iterator<T> iterator) {
        assertArgumentNotNull("iterator", iterator);

        this.iterator = iterator;