throw new NoSuchElementException();
          }
          canRemoveOrSet = true;
          return forwardIterator.next();
        }

        @Override
        public int previousIndex() {
          return nextIndex() - 1;
        }

        @Override
        public void remove() {
          checkRemove(canRemoveOrSet);
          forwardIterator.remove();

    }
    assertEquals(3, iterator.previousIndex());
    assertEquals("4", iterator.previous());
    assertEquals("3", iterator.previous());
    assertEquals("2", iterator.previous());
    assertTrue(iterator.hasPrevious());
    assertEquals("1", iterator.previous());
    assertFalse(iterator.hasPrevious());
    assertEquals(-1, iterator.previousIndex());
    try {
      iterator.previous();

    }
    assertEquals(3, iterator.previousIndex());
    assertEquals("4", iterator.previous());
    assertEquals("3", iterator.previous());
    assertEquals("2", iterator.previous());
    assertTrue(iterator.hasPrevious());
    assertEquals("1", iterator.previous());
    assertFalse(iterator.hasPrevious());
    assertEquals(-1, iterator.previousIndex());
    try {
      iterator.previous();

    ListIterator<String> iterator = Iterators.emptyListIterator();
    assertFalse(iterator.hasNext());
    assertFalse(iterator.hasPrevious());
    assertEquals(0, iterator.nextIndex());
    assertEquals(-1, iterator.previousIndex());
    assertThrows(NoSuchElementException.class, () -> iterator.next());
    assertThrows(NoSuchElementException.class, () -> iterator.previous());

    ListIterator<String> iterator = Iterators.emptyListIterator();
    assertFalse(iterator.hasNext());
    assertFalse(iterator.hasPrevious());
    assertEquals(0, iterator.nextIndex());
    assertEquals(-1, iterator.previousIndex());
    assertThrows(NoSuchElementException.class, () -> iterator.next());
    assertThrows(NoSuchElementException.class, () -> iterator.previous());