private object SlowRequestBody : RequestBody() {
    override fun contentType(): MediaType? = null

    override fun writeTo(sink: BufferedSink) {
      for (i in 0 until 50) {
        sink.writeUtf8("abc")
        sink.flush()
        Thread.sleep(100)
      }
      fail("")
    }
  }

    serverSocket = serverSocketFactory.createServerSocket()
    val serverAddress = InetAddress.getByName("localhost")
    serverSocket!!.bind(InetSocketAddress(serverAddress, 0), 50)
    return InetSocketAddress(serverAddress, serverSocket!!.localPort)
  }

  private fun doServerHandshake(server: HandshakeCertificates): Future<Handshake> {
    return executorService.submit<Handshake> {