/**
   * As described in the <a href="http://idpf.org/epub">International Digital Publishing Forum</a>
   * EPUB is the distribution and interchange format standard for digital publications and
   * documents. This media type is defined in the <a
   * href="http://www.idpf.org/epub/30/spec/epub30-ocf.html">EPUB Open Container Format</a>
   * specification.
   *

    (including a physical distribution medium), accompanied by the
    Corresponding Source fixed on a durable physical medium
    customarily used for software interchange.

    b) Convey the object code in, or embodied in, a physical product
    (including a physical distribution medium), accompanied by a
    written offer, valid for at least three years and valid for as

   *
   * @since 8.0
   */
  public static final byte SUB = 26;

  /**
   * Escape: A control character intended to provide code extension (supplementary characters) in
   * general information interchange. The Escape character itself is a prefix affecting the
   * interpretation of a limited number of contiguously following characters.
   *
   * @since 8.0
   */
  public static final byte ESC = 27;

  /**

   *
   * @since 8.0
   */
  public static final byte SUB = 26;

  /**
   * Escape: A control character intended to provide code extension (supplementary characters) in
   * general information interchange. The Escape character itself is a prefix affecting the
   * interpretation of a limited number of contiguously following characters.
   *
   * @since 8.0
   */
  public static final byte ESC = 27;

  /**

    a) Accompany it with the complete corresponding machine-readable
    source code, which must be distributed under the terms of Sections 1
    and 2 above on a medium customarily used for software interchange; or,

    b) Accompany it with a written offer, valid for at least three
    years, to give any third party, for a charge no more than your cost
    of physically performing source distribution, a complete

it with the complete corresponding machine-readable source code, which
must be distributed under the terms of Sections 1 and 2 above on a
medium customarily used for software interchange.

  If distribution of object code is made by offering access to copy
from a designated place, then offering equivalent access to copy the
source code from the same place satisfies the requirement to

          else -> SequentialExchangeFinder(routePlanner)
        }
    }
  }

  /** Finds a new or pooled connection to carry a forthcoming request and response. */
  internal fun initExchange(chain: RealInterceptorChain): Exchange {
    this.withLock {
      check(expectMoreExchanges) { "released" }
      check(!responseBodyOpen)
      check(!requestBodyOpen)
    }

      }

    open fun receivedResponseAtMillis(receivedResponseAtMillis: Long) =
      apply {
        this.receivedResponseAtMillis = receivedResponseAtMillis
      }

    internal fun initExchange(exchange: Exchange) {
      this.exchange = exchange
      this.trailersFn = { exchange.trailers() }
    }

    open fun build(): Response {
      check(code >= 0) { "code < 0: $code" }