public SortedMap<K, V> subMap(@ParametricNullness K fromKey, @ParametricNullness K toKey) {
    return delegate().subMap(fromKey, toKey);
  }

  @Override
  public SortedMap<K, V> tailMap(@ParametricNullness K fromKey) {
    return delegate().tailMap(fromKey);
  }

  /**
   * A sensible implementation of {@link SortedMap#keySet} in terms of the methods of {@code
   * ForwardingSortedMap}. In many cases, you may wish to override {@link

    }

    @Override
    public NavigableMap<K, V> tailMap(K fromKey, boolean inclusive) {
      assertTrue(Thread.holdsLock(mutex));
      return delegate().tailMap(fromKey, inclusive);
    }

    @Override
    public SortedMap<K, V> tailMap(K fromKey) {
      return tailMap(fromKey, true);
    }

    @Override
    public Comparator<? super K> comparator() {

  }

  /**
   * A sensible definition of {@link #tailMap(Object)} in terms of {@link #tailMap(Object,
   * boolean)}. If you override {@code tailMap(K, boolean)}, you may wish to override {@code
   * tailMap} to forward to this implementation.
   */
  protected SortedMap<K, V> standardTailMap(@ParametricNullness K fromKey) {
    return tailMap(fromKey, true);
  }

  public SortedMap<K, V> subMap(@ParametricNullness K fromKey, @ParametricNullness K toKey) {
    return delegate().subMap(fromKey, toKey);
  }

  @Override
  public SortedMap<K, V> tailMap(@ParametricNullness K fromKey) {
    return delegate().tailMap(fromKey);
  }

  /**
   * A sensible implementation of {@link SortedMap#keySet} in terms of the methods of {@code
   * ForwardingSortedMap}. In many cases, you may wish to override {@link

  }

  @Override
  @CheckForNull
  public Entry<K, V> ceilingEntry(@ParametricNullness K key) {
    return tailMap(key, true).firstEntry();
  }

  @Override
  @CheckForNull
  public Entry<K, V> higherEntry(@ParametricNullness K key) {
    return tailMap(key, false).firstEntry();
  }

  @Override
  @CheckForNull
  public K lowerKey(@ParametricNullness K key) {

  }

  /**
   * A sensible definition of {@link #tailMap(Object)} in terms of {@link #tailMap(Object,
   * boolean)}. If you override {@code tailMap(K, boolean)}, you may wish to override {@code
   * tailMap} to forward to this implementation.
   */
  protected SortedMap<K, V> standardTailMap(@ParametricNullness K fromKey) {
    return tailMap(fromKey, true);
  }

    assertEquals(ImmutableMap.of("dog", 3), filtered.subMap("cat", "emu"));

    assertEquals(ImmutableMap.of("dog", 3), filtered.tailMap("cat"));
    assertEquals(ImmutableMap.of("banana", 6, "dog", 3), filtered.tailMap("banana"));
  }

    TreeBasedTable<String, Integer, Character> table = makeTable();
    populateTable(table);
    return table.rowMap().tailMap("b");
  }

  @Override
  protected Map<String, Map<Integer, Character>> makeEmptyMap() {
    return makeTable().rowMap().tailMap("b");
  }

  @Override
  protected String getKeyNotInPopulatedMap() {
    return "a";
  }

    return subMap(fromKey, true, toKey, false);
  }

  @Override
  public SortedMap<K, V> tailMap(K fromKey) {
    return tailMap(fromKey, true);
  }

  @Override
  public NavigableMap<K, V> tailMap(K fromKey, boolean inclusive) {
    return new SafeTreeMap<>(delegate.tailMap(checkValid(fromKey), inclusive));
  }

  @Override
  public Collection<V> values() {
    return delegate.values();

    return subMap(fromKey, true, toKey, false);
  }

  @Override
  public SortedMap<K, V> tailMap(K fromKey) {
    return tailMap(fromKey, true);
  }

  @Override
  public NavigableMap<K, V> tailMap(K fromKey, boolean inclusive) {
    return new SafeTreeMap<>(delegate.tailMap(checkValid(fromKey), inclusive));
  }

  @Override
  public Collection<V> values() {
    return delegate.values();