* [Request.tag]. Use null to remove any existing tag assigned for [T].
     *
     * Use this API to attach timing, debugging, or other application data to a request so that
     * you may read it in interceptors, event listeners, or callbacks.
     */
    @JvmName("reifiedTag")
    inline fun <reified T : Any> tag(tag: T?): Builder = tag(T::class, tag)

    /**

  private var protocol: Protocol?,
  private var source: BufferedSource?,
  private var sink: BufferedSink?,
  private val pingIntervalMillis: Int,
  internal val connectionListener: ConnectionListener,
) : Http2Connection.Listener(), Connection, ExchangeCodec.Carrier {
  private var http2Connection: Http2Connection? = null

  internal val lock: ReentrantLock = ReentrantLock()

  // These properties are guarded by [lock].

  /**

   * [requestBodyOpen], [responseBodyOpen], and [expectMoreExchanges].
   *
   * This will release the connection if it is still held.
   *
   * It will also notify the listener that the call completed; either successfully or
   * unsuccessfully.
   *
   * If the call was canceled or timed out, this will wrap [e] in an exception that provides that

  @Synchronized fun receivedPongCount(): Int = receivedPongCount

  @Throws(IOException::class)
  override fun onReadMessage(text: String) {
    listener.onMessage(this, text)
  }

  @Throws(IOException::class)
  override fun onReadMessage(bytes: ByteString) {
    listener.onMessage(this, bytes)
  }

  @Synchronized override fun onReadPing(payload: ByteString) {

        .validityInterval(1, 2)
        .build()
    var client = buildClient(clientCert, clientIntermediateCa.certificate)
    val listener = RecordingEventListener()
    client =
      client.newBuilder()
        .eventListener(listener)
        .build()
    val socketFactory = buildServerSslSocketFactory()
    server.useHttps(socketFactory)
    server.requireClientAuth()

     * This will overwrite any previously set status, body, or streamHandler.
     */
    fun webSocketUpgrade(listener: WebSocketListener) =
      apply {
        status = "HTTP/1.1 101 Switching Protocols"
        setHeader("Connection", "Upgrade")
        setHeader("Upgrade", "websocket")
        webSocketListener = listener
      }

    /**

    server.processNextFrame()
    client.listener.assertClosing(1000, "Hello!")
    server.listener.assertClosing(1000, "Hi!")
    client.webSocket!!.finishReader()
    server.webSocket!!.finishReader()
    client.listener.assertClosed(1000, "Hello!")
    server.listener.assertClosed(1000, "Hi!")
    taskFaker.runTasks()
    assertThat(client.closed).isTrue()

    // In the process we made one successful connection attempt.
    assertThat(listener.recordedEventTypes().filter { it == "ConnectStart" }).hasSize(2)
    assertThat(listener.recordedEventTypes().filter { it == "ConnectFailed" }).hasSize(1)
    assertThat(listener.recordedEventTypes().filter { it == "ConnectEnd" }).hasSize(1)
  }

  @Test
  fun reachesIpv6WhenIpv4IsDown() {

        .build().also {
          listener.satisfactionFailure(call, it)
        }
    }

    // If we don't need the network, we're done.
    if (networkRequest == null) {
      return cacheResponse!!.newBuilder()
        .cacheResponse(cacheResponse.stripBody())
        .build().also {
          listener.cacheHit(call, it)
        }
    }

    if (cacheResponse != null) {

  val dispatcher = Dispatcher(executor)
  val listener = RecordingEventListener()
  var client =
    clientTestRule.newClientBuilder()
      .dns { throw UnknownHostException() }
      .dispatcher(dispatcher)
      .eventListenerFactory(clientTestRule.wrap(listener))
      .build()

  @BeforeEach
  fun setUp() {
    dispatcher.maxRequests = 20
    dispatcher.maxRequestsPerHost = 10
    listener.forbidLock(dispatcher)
  }

  @Test