return backingSet;
    }

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

    @Override
    public int hashCode() {
      return standardHashCode();
    }

    @Override
    public boolean addAll(Collection<? extends T> collection) {
      return standardAddAll(collection);
    }

    @Override
    public void clear() {
      standardClear();

    }

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

    @Override
    public int hashCode() {
      return standardHashCode();
    }

    @Override
    public int indexOf(Object element) {
      return standardIndexOf(element);
    }

    @Override
    public int lastIndexOf(Object element) {

    }

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

    @Override
    public int hashCode() {
      return standardHashCode();
    }

    @Override
    public boolean add(E element) {
      return standardAdd(element);
    }

    @Override
    public boolean addAll(Collection<? extends E> collection) {

      return backingSet;
    }

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

    @Override
    public int hashCode() {
      return standardHashCode();
    }

    @Override
    public boolean addAll(Collection<? extends T> collection) {
      return standardAddAll(collection);
    }

    @Override
    public void clear() {
      standardClear();

   * {@link #iterator}, you may wish to override {@link #equals} to forward to this implementation.
   *
   * @since 7.0
   */
  protected int standardHashCode() {
    return Sets.hashCodeImpl(this);
  }

   * {@link #iterator}, you may wish to override {@link #equals} to forward to this implementation.
   *
   * @since 7.0
   */
  protected int standardHashCode() {
    return Sets.hashCodeImpl(this);
  }

    }

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

    @Override
    public int hashCode() {
      return standardHashCode();
    }

    @Override
    public boolean add(E element) {
      return standardAdd(element);
    }

    @Override
    public boolean addAll(Collection<? extends E> collection) {

   * #getValue()}. If you override either of these methods, you may wish to override {@link
   * #hashCode()} to forward to this implementation.
   *
   * @since 7.0
   */
  protected int standardHashCode() {
    K k = getKey();
    V v = getValue();
    return ((k == null) ? 0 : k.hashCode()) ^ ((v == null) ? 0 : v.hashCode());
  }

  /**

   * {@link #iterator}, you may wish to override {@link #hashCode} to forward to this
   * implementation.
   *
   * @since 7.0
   */
  protected int standardHashCode() {
    return Lists.hashCodeImpl(this);
  }

   * #getValue()}. If you override either of these methods, you may wish to override {@link
   * #hashCode()} to forward to this implementation.
   *
   * @since 7.0
   */
  protected int standardHashCode() {
    K k = getKey();
    V v = getValue();
    return ((k == null) ? 0 : k.hashCode()) ^ ((v == null) ? 0 : v.hashCode());
  }

  /**