}

  /**
   * A sensible definition of {@link #contains} in terms of {@link #count}. If you override {@link
   * #count}, you may wish to override {@link #contains} to forward to this implementation.
   *
   * @since 7.0
   */
  @Override
  protected boolean standardContains(@Nullable Object object) {
    return count(object) > 0;
  }

  /**

  @Override
  protected abstract NavigableSet<E> delegate();

  @Override
  public @Nullable E lower(@ParametricNullness E e) {
    return delegate().lower(e);
  }

  /**
   * A sensible definition of {@link #lower} in terms of the {@code descendingIterator} method of
   * {@link #headSet(Object, boolean)}. If you override {@link #headSet(Object, boolean)}, you may

    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
  protected abstract NavigableMap<K, V> delegate();

  @Override
  public @Nullable Entry<K, V> lowerEntry(@ParametricNullness K key) {
    return delegate().lowerEntry(key);
  }

  /**
   * 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.

  @Override
  protected abstract NavigableMap<K, V> delegate();

  @Override
  public @Nullable Entry<K, V> lowerEntry(@ParametricNullness K key) {
    return delegate().lowerEntry(key);
  }

  /**
   * 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.

  public boolean equals(@Nullable Object object) {
    return object == this || delegate().equals(object);
  }

  @Override
  public int hashCode() {
    return delegate().hashCode();
  }

  /**
   * A sensible definition of {@link #removeAll} in terms of {@link #iterator} and {@link #remove}.
   * If you override {@code iterator} or {@code remove}, you may wish to override {@link #removeAll}
   * to forward to this implementation.
   *

  }

  @Override
  public @Nullable E peek() {
    return delegate().peek();
  }

  @Override
  @ParametricNullness
  public E element() {
    return delegate().element();
  }

  /**
   * A sensible definition of {@link #offer} in terms of {@link #add}. If you override {@link #add},
   * you may wish to override {@link #offer} to forward to this implementation.
   *
   * @since 7.0
   */

    return null;
  }

  /**
   * A sensible definition of {@link #clear} in terms of the {@code iterator} method of {@link
   * #entrySet}. In many cases, you may wish to override {@link #clear} to forward to this
   * implementation.
   *
   * @since 7.0
   */
  protected void standardClear() {
    Iterators.clear(entrySet().iterator());
  }

  /**

  @Override
  protected abstract NavigableSet<E> delegate();

  @Override
  public @Nullable E lower(@ParametricNullness E e) {
    return delegate().lower(e);
  }

  /**
   * A sensible definition of {@link #lower} in terms of the {@code descendingIterator} method of
   * {@link #headSet(Object, boolean)}. If you override {@link #headSet(Object, boolean)}, you may

  @Override
  public boolean equals(@Nullable Object object) {
    return delegate().equals(object);
  }

  @Override
  public int hashCode() {
    return delegate().hashCode();
  }

  /**
   * A sensible definition of {@link #equals(Object)} in terms of {@link #getKey()} and {@link
   * #getValue()}. If you override either of these methods, you may wish to override {@link
   * #equals(Object)} to forward to this implementation.
   *