*
   * @since 9.0 (was type {@code int} before 12.0)
   */
  public static final char MAX = 127;

  /** A bit mask which selects the bit encoding ASCII character case. */
  private static final char CASE_MASK = 0x20;

  /**
   * Returns a copy of the input string in which all {@linkplain #isUpperCase(char) uppercase ASCII
   * characters} have been converted to lowercase. All other characters are copied without
   * modification.

    continuation.padding = padding
    continuation.flags = flags
    continuation.streamId = streamId

    // TODO: Concat multi-value headers with 0x0, except COOKIE, which uses 0x3B, 0x20.
    // http://tools.ietf.org/html/draft-ietf-httpbis-http2-17#section-8.1.2.5
    hpackReader.readHeaders()
    return hpackReader.getAndResetHeaderList()
  }

  @Throws(IOException::class)

  }

  public void testBase32InvalidDecodings() {
    // These contain bytes not in the decodabet.
    assertFailsToDecode(base32(), "A ", "Unrecognized character: 0x20");
    assertFailsToDecode(base32(), "Wf2!", "Unrecognized character: f");
    // This sentence just isn't base32() encoded.
    assertFailsToDecode(base32(), "let's not talk of love or chains!");

   * @return {@code true} if the argument is a 6to4 address
   */
  public static boolean is6to4Address(Inet6Address ip) {
    byte[] bytes = ip.getAddress();
    return (bytes[0] == (byte) 0x20) && (bytes[1] == (byte) 0x02);
  }

  /**
   * Returns the IPv4 address embedded in a 6to4 address.
   *
   * @param ip {@link Inet6Address} to be examined for embedded IPv4 in 6to4 address

    val buffer = Buffer()
    buffer.writeUtf8CodePoint(0x89)
    buffer.writeUtf8CodePoint(0x50)
    buffer.writeUtf8CodePoint(0x4e)
    buffer.writeUtf8CodePoint(0x47)
    buffer.writeUtf8CodePoint(0x0d)
    buffer.writeUtf8CodePoint(0x0a)
    buffer.writeUtf8CodePoint(0x1a)
    buffer.writeUtf8CodePoint(0x0a)
    server.enqueue(
      MockResponse
        .Builder()
        .body(buffer)

      // TODO(cpovirk): Use SourceCodeEscapers if it is added to Guava.
      StringBuilder escapedInput = new StringBuilder();
      for (char c : input.toCharArray()) {
        if (c >= 0x20 && c <= 0x7E) {
          escapedInput.append(c);
        } else {
          escapedInput.append(String.format("\\u%04x", (int) c));
        }
      }

    assertFailsWith<IllegalArgumentException> {
      Request.Builder().addHeader("a b", "c")
    }.also { expected ->
      assertThat(expected.message).isEqualTo("Unexpected char 0x20 at 1 in header name: a b")
    }
  }

  @Test
  fun requestHeaderNameWithTabForbidden() {
    assertFailsWith<IllegalArgumentException> {
      Request.Builder().addHeader("a\tb", "c")