* #containsKey} to forward to this implementation.
   *
   * @since 7.0
   */
  @Override
  protected boolean standardContainsKey(@CheckForNull Object key) {
    try {
      // any CCE or NPE will be caught
      @SuppressWarnings({"unchecked", "nullness"})
      SortedMap<@Nullable Object, V> self = (SortedMap<@Nullable Object, V>) this;
      Object ceilingKey = self.tailMap(key).firstKey();

   * #containsKey} to forward to this implementation.
   *
   * @since 7.0
   */
  @Override
  protected boolean standardContainsKey(@CheckForNull Object key) {
    try {
      // any CCE or NPE will be caught
      @SuppressWarnings({"unchecked", "nullness"})
      SortedMap<@Nullable Object, V> self = (SortedMap<@Nullable Object, V>) this;
      Object ceilingKey = self.tailMap(key).firstKey();