/**
   * 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.
   */
  @CheckForNull
  protected Entry<E> standardFirstEntry() {
    Iterator<Entry<E>> entryIterator = entrySet().iterator();
    if (!entryIterator.hasNext()) {
      return null;
    }

      @ParametricNullness E a, @ParametricNullness E b, @ParametricNullness E c, E... rest) {
    return forwardOrder.max(a, b, c, rest);
  }

  @Override
  public <E extends T> E min(Iterator<E> iterator) {
    return forwardOrder.max(iterator);
  }

  @Override
  public <E extends T> E min(Iterable<E> iterable) {
    return forwardOrder.max(iterable);
  }

  @Override

   * @throws ClassCastException if the parameters are not <i>mutually comparable</i> under this
   *     ordering.
   * @since 11.0
   */
  @ParametricNullness
  public <E extends T> E min(Iterator<E> iterator) {
    // let this throw NoSuchElementException as necessary
    E minSoFar = iterator.next();

    while (iterator.hasNext()) {
      minSoFar = this.<E>min(minSoFar, iterator.next());
    }

  @CollectionFeature.Require(absent = SUPPORTS_REMOVE)
  @CollectionSize.Require(absent = ZERO)
  public void testIteratorRemove_unsupported() {
    Iterator<E> iterator = collection.iterator();
    iterator.next();
    assertThrows(UnsupportedOperationException.class, () -> iterator.remove());
    expectUnchanged();
    assertTrue(collection.contains(e0()));
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)

  }

  @CollectionSize.Require(ONE)
  @CollectionFeature.Require(SUPPORTS_ITERATOR_REMOVE)
  public void testEntrySetIteratorRemove() {
    Set<Entry<K, V>> entrySet = getMap().entrySet();
    Iterator<Entry<K, V>> entryItr = entrySet.iterator();
    assertEquals(e0(), entryItr.next());
    entryItr.remove();
    assertTrue(getMap().isEmpty());
    assertFalse(entrySet.contains(e0()));
  }

  }

  @CollectionSize.Require(ONE)
  @CollectionFeature.Require(SUPPORTS_ITERATOR_REMOVE)
  public void testEntrySetIteratorRemove() {
    Set<Entry<K, V>> entrySet = getMap().entrySet();
    Iterator<Entry<K, V>> entryItr = entrySet.iterator();
    assertEquals(e0(), entryItr.next());
    entryItr.remove();
    assertTrue(getMap().isEmpty());
    assertFalse(entrySet.contains(e0()));
  }

            @Override
            public int compare(K o1, K o2) {
              return ((Comparable) o1).compareTo(o2);
            }
          };
    }
    Iterator<Entry<K, V>> entryItr = navigableMap.entrySet().iterator();
    Entry<K, V> prevEntry = entryItr.next();
    while (entryItr.hasNext()) {
      Entry<K, V> nextEntry = entryItr.next();

  @CollectionFeature.Require(SUPPORTS_ITERATOR_REMOVE)
  @CollectionSize.Require(absent = ZERO)
  public void testKeySetIteratorRemove() {
    int initialSize = getNumElements();
    Iterator<K> iterator = getMap().keySet().iterator();
    iterator.next();
    iterator.remove();
    assertEquals(initialSize - 1, getMap().size());
    assertEquals(initialSize - 1, getMap().inverse().size());
  }

    }

    @Override
    Iterator<Entry<K, V>> entryIterator() {
      return Iterators.filter(unfiltered.entrySet().iterator(), entryPredicate);
    }

    @Override
    Iterator<Entry<K, V>> descendingEntryIterator() {
      return Iterators.filter(unfiltered.descendingMap().entrySet().iterator(), entryPredicate);
    }

    @Override
    public int size() {

    }

    @Override
    Iterator<Entry<K, V>> entryIterator() {
      return Iterators.filter(unfiltered.entrySet().iterator(), entryPredicate);
    }

    @Override
    Iterator<Entry<K, V>> descendingEntryIterator() {
      return Iterators.filter(unfiltered.descendingMap().entrySet().iterator(), entryPredicate);
    }

    @Override
    public int size() {