/**
   * A sensible definition of {@link #lowerEntry} in terms of the {@code lastEntry()} of {@link
   * #headMap(Object, boolean)}. If you override {@code headMap}, you may wish to override {@code
   * lowerEntry} to forward to this implementation.
   */
  protected @Nullable Entry<K, V> standardLowerEntry(@ParametricNullness K key) {
    return headMap(key, false).lastEntry();
  }

  @Override

  /**
   * A sensible definition of {@link #lowerEntry} in terms of the {@code lastEntry()} of {@link
   * #headMap(Object, boolean)}. If you override {@code headMap}, you may wish to override {@code
   * lowerEntry} to forward to this implementation.
   */
  protected @Nullable Entry<K, V> standardLowerEntry(@ParametricNullness K key) {
    return headMap(key, false).lastEntry();
  }

  @Override

    }

    @Override
    public NavigableMap<K, Collection<V>> headMap(@ParametricNullness K toKey) {
      return headMap(toKey, false);
    }

    @Override
    public NavigableMap<K, Collection<V>> headMap(@ParametricNullness K toKey, boolean inclusive) {
      return new NavigableAsMap(sortedMap().headMap(toKey, inclusive));
    }

    @Override

        return tmp;
      }
    }
    return null;
  }

  @Override
  public ImmutableSortedMap<K, V> headMap(K toKey) {
    checkNotNull(toKey);
    return newView(sortedDelegate.headMap(toKey));
  }

  ImmutableSortedMap<K, V> headMap(K toKey, boolean inclusive) {
    checkNotNull(toKey);
    if (inclusive) {
      K tmp = higher(toKey);
      if (tmp == null) {

        assertThat(navigableMap.headMap(key, inclusive).entrySet())
            .containsExactlyElementsIn(expected.headMap(key, inclusive).entrySet())
            .inOrder();
        assertThat(navigableMap.tailMap(key, inclusive).entrySet())
            .containsExactlyElementsIn(expected.tailMap(key, inclusive).entrySet())
            .inOrder();
        assertThat(navigableMap.headMap(key, inclusive).descendingMap().entrySet())

          if (subRange.isEmpty()) {
            return emptyIterator();
          }
          Iterator<RangeMapEntry<K, V>> backingItr =
              entriesByLowerBound
                  .headMap(subRange.upperBound, false)
                  .descendingMap()
                  .values()
                  .iterator();
          return new AbstractIterator<Entry<Range<K>, V>>() {

            @Override

     */
    SortedMap<K, V> createSubMap(SortedMap<K, V> map, K firstExclusive, K lastExclusive) {
      if (from == Bound.NO_BOUND && to == Bound.EXCLUSIVE) {
        return map.headMap(lastExclusive);
      } else if (from == Bound.INCLUSIVE && to == Bound.NO_BOUND) {
        return map.tailMap(firstInclusive);
      } else if (from == Bound.INCLUSIVE && to == Bound.EXCLUSIVE) {

  }

  public void testRowKeyMapHeadMap() {
    sortedTable = create("foo", 1, 'a', "bar", 1, 'b', "foo", 3, 'c');
    Map<String, Map<Integer, Character>> map = sortedTable.rowMap().headMap("cat");
    assertEquals(1, map.size());
    assertEquals(ImmutableMap.of(1, 'b'), map.get("bar"));
    map.clear();
    assertTrue(map.isEmpty());
    assertEquals(singleton("foo"), sortedTable.rowKeySet());
  }

          if (subRange.isEmpty()) {
            return emptyIterator();
          }
          Iterator<RangeMapEntry<K, V>> backingItr =
              entriesByLowerBound
                  .headMap(subRange.upperBound, false)
                  .descendingMap()
                  .values()
                  .iterator();
          return new AbstractIterator<Entry<Range<K>, V>>() {

            @Override