@Throws(IOException::class)
  fun writePing(payload: ByteString) {
    writeControlFrame(OPCODE_CONTROL_PING, payload)
  }

  /** Send a pong with the supplied [payload]. */
  @Throws(IOException::class)
  fun writePong(payload: ByteString) {
    writeControlFrame(OPCODE_CONTROL_PONG, payload)
  }

  /**
   * Send a close frame with optional code and reason.
   *
   * @param code Status code as defined by

    assertData("898560b420bb28d14cd70f")
  }

  @Test fun serverEmptyPong() {
    serverWriter.writePong(EMPTY)
    assertData("8a00")
  }

  @Test fun clientEmptyPong() {
    clientWriter.writePong(EMPTY)
    assertData("8a8060b420bb")
  }

  @Test fun serverPongWithPayload() {
    serverWriter.writePong("Hello".encodeUtf8())
    assertData("8a0548656c6c6f")
  }

  @Test fun clientPongWithPayload() {

    val from = nextAddress
    nextAddress += count
    return (from until nextAddress)
      .map {
        return@map InetAddress.getByAddress(
          Buffer().writeLong(0L).writeLong(it).readByteArray(),
        )
      }
  }

  }

  /**
   * Writes a {@code long} as specified by {@link DataOutputStream#writeLong(long)}, except using
   * little-endian byte order.
   *
   * @throws IOException if an I/O error occurs
   */
  @Override
  public void writeLong(long v) throws IOException {
    ((DataOutputStream) out).writeLong(Long.reverseBytes(v));
  }

  /**

  @Override
  void writeByte(int v);

  @Override
  void writeShort(int v);

  @Override
  void writeChar(int v);

  @Override
  void writeInt(int v);

  @Override
  void writeLong(long v);

  @Override
  void writeFloat(float v);

  @Override
  void writeDouble(double v);

  @Override
  void writeChars(String s);

  @Override
  void writeUTF(String s);

  /**

  @Override
  void writeByte(int v);

  @Override
  void writeShort(int v);

  @Override
  void writeChar(int v);

  @Override
  void writeInt(int v);

  @Override
  void writeLong(long v);

  @Override
  void writeFloat(float v);

  @Override
  void writeDouble(double v);

  @Override
  void writeChars(String s);

  @Override
  void writeUTF(String s);

  /**

  fun writeBoolean(b: Boolean) {
    sink().writeByte(if (b) -1 else 0)
  }

  fun writeBigInteger(value: BigInteger) {
    sink().write(value.toByteArray())
  }

  fun writeLong(v: Long) {
    val sink = sink()

    val lengthBitCount: Int =
      if (v < 0L) {
        65 - java.lang.Long.numberOfLeadingZeros(v xor -1L)
      } else {

    out.writeByte(100);
    out.writeByte(-100);
    out.writeByte((byte) 200);
    out.writeChar('a');
    out.writeShort((short) -30000);
    out.writeShort((short) 50000);
    out.writeInt(0xCAFEBABE);
    out.writeLong(0xDEADBEEFCAFEBABEL);
    out.writeUTF("Herby Derby");
    out.writeFloat(Float.intBitsToFloat(0xCAFEBABE));
    out.writeDouble(Double.longBitsToDouble(0xDEADBEEFCAFEBABEL));

    byte[] data = baos.toByteArray();

    out.writeByte(100);
    out.writeByte(-100);
    out.writeByte((byte) 200);
    out.writeChar('a');
    out.writeShort((short) -30000);
    out.writeShort((short) 50000);
    out.writeInt(0xCAFEBABE);
    out.writeLong(0xDEADBEEFCAFEBABEL);
    out.writeUTF("Herby Derby");
    out.writeFloat(Float.intBitsToFloat(0xCAFEBABE));
    out.writeDouble(Double.longBitsToDouble(0xDEADBEEFCAFEBABEL));

    byte[] data = baos.toByteArray();

  private fun writeHeader(
    prefix: ByteString,
    upstreamSize: Long,
    metadataSize: Long,
  ) {
    val header =
      Buffer().apply {
        write(prefix)
        writeLong(upstreamSize)
        writeLong(metadataSize)
        require(size == FILE_HEADER_SIZE)
      }

    val fileOperator = FileOperator(file!!.channel)
    fileOperator.write(0, header, FILE_HEADER_SIZE)
  }