}

    /**
     * Append content to the message buffer.
     *
     * @param value the content to append
     * @param start the starting index of the subsequence to be appended
     * @param end the end index of the subsequence to be appended
     * @return the current builder
     */
    @Nonnull
    default MessageBuilder a(CharSequence value, int start, int end) {

   * some cases it may alter the input. For example, if the factory returns a sliced view of a
   * source created with some given bytes, this method would return a subsequence of the given
   * (byte[]) data.
   */
  T getExpected(T data);

  /** Cleans up anything created when creating the source or sink. */
  void tearDown() throws IOException;

   * some cases it may alter the input. For example, if the factory returns a sliced view of a
   * source created with some given bytes, this method would return a subsequence of the given
   * (byte[]) data.
   */
  T getExpected(T data);

  /** Cleans up anything created when creating the source or sink. */
  void tearDown() throws IOException;

      return length;
    }

    @Override
    public char charAt(int index) {
      return chunks.get(index >> chunkShift).charAt(index & chunkMask);
    }

    @Override
    public CharSequence subSequence(int start, int end) {
      throw new UnsupportedOperationException();
    }

    @Override
    public String toString() {
      StringBuilder sb = new StringBuilder(length);