private var sslSocketFactory: SSLSocketFactory? = null
  private var clientAuth = CLIENT_AUTH_NONE

  /**
   * The dispatcher used to respond to HTTP requests. The default dispatcher is a [QueueDispatcher],
   * which serves a fixed sequence of responses from a [queue][enqueue].
   *
   * Other dispatchers can be configured. They can vary the response based on timing or the content
   * of the request.
   */