buildConnectionPool(
            connectionListener = connectionListener,
            taskRunner = taskRunner,
          ),
        ).dispatcher(Dispatcher(backend.executor))
        .taskRunnerInternal(taskRunner)
    } else {
      OkHttpClient
        .Builder()
        .connectionPool(ConnectionPool(connectionListener = connectionListener))
    }

  private val javaNetSocket: JavaNetSocket,
  private val handshake: Handshake?,
  private val protocol: Protocol,
  private val socket: BufferedSocket,
  private val pingIntervalMillis: Int,
  internal val connectionListener: ConnectionListener,
) : Http2Connection.Listener(),
  Connection,
  ExchangeCodec.Carrier,
  Lockable {
  private var http2Connection: Http2Connection? = null

  // These properties are guarded by `this`.

  /**

        toClose.closeQuietly()
        connectionListener.connectionClosed(connection)
      } else if (noNewExchangesEvent) {
        connectionListener.noNewExchanges(connection)
      }
    }
    return null
  }

  fun put(connection: RealConnection) {
    connection.assertLockHeld()

    connections.add(connection)
//    connection.queueEvent { connectionListener.connectEnd(connection) }
    scheduleCloser()

          javaNetSocket = javaNetSocket!!,
          handshake = handshake,
          protocol = protocol!!,
          socket = socket,
          pingIntervalMillis = pingIntervalMillis,
          connectionListener = connectionPool.connectionListener,
        )
      this.connection = connection
      connection.start()

      // Success.
      call.eventListener.connectEnd(call, route.socketAddress, route.proxy, protocol)

      override val badValue: ConnectionPool =
        ConnectionPool(
          keepAliveDuration = 1,
          timeUnit = TimeUnit.MINUTES,
          connectionListener =
            object : ConnectionListener() {
              override fun connectStart(
                route: Route,
                call: Call,
              ): Unit = TODO()
            },
        )

    that this function is sensitive to when it is called: the response body must be supplied before
    it can be compressed.

 *  Breaking: Remove `AddressPolicy`, `AsyncDns`, and `ConnectionListener` from the public API. We
    intend to ship a public API for these features, but we don't want to hold OkHttp 5.0.0 until
    those APIs are stable.

    toClose?.closeQuietly()
    call.eventListener.connectionReleased(call, candidate)
    candidate.connectionListener.connectionReleased(candidate, call)
    if (toClose != null) {
      candidate.connectionListener.connectionClosed(candidate)
    } else if (noNewExchangesEvent) {
      candidate.connectionListener.noNewExchanges(candidate)
    }
    return null
  }

        }
      if (this.connection == null) {
        toClose?.closeQuietly()
        eventListener.connectionReleased(this, connection)
        connection.connectionListener.connectionReleased(connection, this)
        if (toClose != null) {
          connection.connectionListener.connectionClosed(connection)
        }
      } else {
        check(toClose == null) // If we still have a connection we shouldn't be closing any sockets.