val s = sslSocket as BCSSLSocket

    return when (val protocol = s.applicationProtocol) {
      null, "" -> null
      else -> protocol
    }
  }

  override fun configureTlsExtensions(
    sslSocket: SSLSocket,
    hostname: String?,
    protocols: List<Protocol>,
  ) {
    // No TLS extensions if the socket class is custom.
    if (matchesSocket(sslSocket)) {

      RequestBodyEnd::class,
      ConnectionReleased::class,
      CallEnd::class,
    )
  }

  private fun enableTls(vararg protocols: Protocol) {
    client =
      client
        .newBuilder()
        .protocols(protocols.toList())
        .sslSocketFactory(
          handshakeCertificates.sslSocketFactory(),
          handshakeCertificates.trustManager,

        call.eventListener.secureConnectEnd(call, handshake)
      } else {
        javaNetSocket = rawSocket
        protocol =
          when {
            Protocol.H2_PRIOR_KNOWLEDGE in route.address.protocols -> Protocol.H2_PRIOR_KNOWLEDGE
            else -> Protocol.HTTP_1_1
          }
      }

      val connection =
        RealConnection(
          taskRunner = taskRunner,

     * Returns the concatenation of 8-bit, length prefixed protocol names.
     * http://tools.ietf.org/html/draft-agl-tls-nextprotoneg-04#page-4
     */
    fun concatLengthPrefixed(protocols: List<Protocol>): ByteArray {
      val result = Buffer()
      for (protocol in alpnProtocolNames(protocols)) {
        result.writeByte(protocol.length)
        result.writeUtf8(protocol)
      }
      return result.readByteArray()
    }

    val dns: Dns = address.dns()
    val socketFactory: SocketFactory = address.socketFactory()
    val proxyAuthenticator: Authenticator = address.proxyAuthenticator()
    val protocols: List<Protocol> = address.protocols()
    val connectionSpecs: List<ConnectionSpec> = address.connectionSpecs()
    val proxySelector: ProxySelector = address.proxySelector()
    val proxy: Proxy? = address.proxy()

            sslSocketFactory(
              sslSocketFactory,
              handshakeCertificates.trustManager,
            )

            when (socketMode.protocol) {
              HTTP_2 -> protocols(listOf(HTTP_2, HTTP_1_1))
              HTTP_1_1 -> protocols(listOf(HTTP_1_1))
              else -> TODO()
            }

            val serverSslSocketFactory =

  override fun configureTlsExtensions(
    sslSocket: SSLSocket,
    hostname: String?,
    protocols: List<Protocol>,
  ) {
    getDelegate(sslSocket)?.configureTlsExtensions(sslSocket, hostname, protocols)
  }

  override fun getSelectedProtocol(sslSocket: SSLSocket): String? = getDelegate(sslSocket)?.getSelectedProtocol(sslSocket)

    val i = HttpLoggingInterceptor()

    builder.interceptors().add(i)
    builder.networkInterceptors().add(i)
  }

  @Test
  fun protocol() {
    var protocol: Protocol = Protocol.HTTP_2
    protocol = Protocol.get("")
  }

  @Test
  fun pushPromise() {
    val pushPromise: PushPromise = PushPromise("", "", headersOf(), MockResponse())

  override fun configureTlsExtensions(
    sslSocket: SSLSocket,
    hostname: String?,
    protocols: List<Protocol>,
  ) {
    try {
      SSLSockets.setUseSessionTickets(sslSocket, true)

      val sslParameters = sslSocket.sslParameters

      // Enable ALPN.
      sslParameters.applicationProtocols = Platform.alpnProtocolNames(protocols).toTypedArray()

      sslSocket.sslParameters = sslParameters

      .assertSuccessful()
      .assertCode(200)
  }

  private fun enableProtocol(protocol: Protocol) {
    enableTls()
    client =
      client
        .newBuilder()
        .protocols(listOf(protocol, Protocol.HTTP_1_1))
        .build()
    server1.protocols = client.protocols
    server2.protocols = client.protocols
  }

  private fun enableTls() {
    client =
      client