length: Int,
      flags: Int,
      padding: Int,
    ): Int {
      var result = length
      if (flags and FLAG_PADDED != 0) result-- // Account for reading the padding length.
      if (padding > result) {
        throw IOException("PROTOCOL_ERROR padding $padding > remaining length $result")
      }
      result -= padding
      return result
    }
  }

   * characters as specified by <a href="http://tools.ietf.org/html/rfc4648#section-3.2">RFC 4648
   * section 3.2</a>, Padding of Encoded Data.
   */
  public abstract BaseEncoding omitPadding();

  /**
   * Returns an encoding that behaves equivalently to this encoding, but uses an alternate character
   * for padding.
   *

    val paddingLength = 254
    val padding = ByteArray(paddingLength)
    Arrays.fill(padding, 0.toByte())
    writeMedium(frame, dataLength + paddingLength + 1)
    frame.writeByte(Http2.TYPE_DATA)
    frame.writeByte(FLAG_PADDED)
    frame.writeInt(expectedStreamId and 0x7fffffff)
    frame.writeByte(paddingLength)
    frame.write(expectedData)
    frame.write(padding)

   * @return an array containing the values of {@code array}, with guaranteed minimum length {@code
   *     minLength}
   */
  public static boolean[] ensureCapacity(boolean[] array, int minLength, int padding) {
    checkArgument(minLength >= 0, "Invalid minLength: %s", minLength);
    checkArgument(padding >= 0, "Invalid padding: %s", padding);

   * @return an array containing the values of {@code array}, with guaranteed minimum length {@code
   *     minLength}
   */
  public static boolean[] ensureCapacity(boolean[] array, int minLength, int padding) {
    checkArgument(minLength >= 0, "Invalid minLength: %s", minLength);
    checkArgument(padding >= 0, "Invalid padding: %s", padding);

   * @return an array containing the values of {@code array}, with guaranteed minimum length {@code
   *     minLength}
   */
  public static char[] ensureCapacity(char[] array, int minLength, int padding) {
    checkArgument(minLength >= 0, "Invalid minLength: %s", minLength);
    checkArgument(padding >= 0, "Invalid padding: %s", padding);

   * @return an array containing the values of {@code array}, with guaranteed minimum length {@code
   *     minLength}
   */
  public static short[] ensureCapacity(short[] array, int minLength, int padding) {
    checkArgument(minLength >= 0, "Invalid minLength: %s", minLength);
    checkArgument(padding >= 0, "Invalid padding: %s", padding);

   * @return an array containing the values of {@code array}, with guaranteed minimum length {@code
   *     minLength}
   */
  public static short[] ensureCapacity(short[] array, int minLength, int padding) {
    checkArgument(minLength >= 0, "Invalid minLength: %s", minLength);
    checkArgument(padding >= 0, "Invalid padding: %s", padding);

   * @return an array containing the values of {@code array}, with guaranteed minimum length {@code
   *     minLength}
   */
  public static char[] ensureCapacity(char[] array, int minLength, int padding) {
    checkArgument(minLength >= 0, "Invalid minLength: %s", minLength);
    checkArgument(padding >= 0, "Invalid padding: %s", padding);

   * @return an array containing the values of {@code array}, with guaranteed minimum length {@code
   *     minLength}
   */
  public static float[] ensureCapacity(float[] array, int minLength, int padding) {
    checkArgument(minLength >= 0, "Invalid minLength: %s", minLength);
    checkArgument(padding >= 0, "Invalid padding: %s", padding);