OkHttpClient
        .Builder()
        .protocols(listOf(Protocol.H2_PRIOR_KNOWLEDGE, Protocol.H2_PRIOR_KNOWLEDGE))
    }.also { expected ->
      assertThat(expected.message).isEqualTo(
        "protocols containing h2_prior_knowledge cannot use other protocols: " +
          "[h2_prior_knowledge, h2_prior_knowledge]",
      )
    }
  }

   *
   * See also [Starting HTTP/2 with Prior Knowledge][rfc_7540_34].
   *
   * [rfc_7540_34]: https://datatracker.ietf.org/doc/html/rfc7540#autoid-10
   */
  H2_PRIOR_KNOWLEDGE("h2_prior_knowledge"),

  /**
   * QUIC (Quick UDP Internet Connection) is a new multiplexed and secure transport atop UDP,
   * designed from the ground up and optimized for HTTP/2 semantics. HTTP/1.1 semantics are layered

      listOf(
        localhostIpv4,
        localhostIpv6,
        TestUtil.UNREACHABLE_ADDRESS_IPV4.address,
      )
    serverIpv4.protocols = listOf(Protocol.H2_PRIOR_KNOWLEDGE)
    serverIpv6.protocols = listOf(Protocol.H2_PRIOR_KNOWLEDGE)

    // Yield the first IP address so the second IP address completes first.
    val firstConnectLatch = CountDownLatch(1)
    val socketFactory =

      server.protocols = listOf(Protocol.H2_PRIOR_KNOWLEDGE, Protocol.H2_PRIOR_KNOWLEDGE)
      fail<Any>()
    } catch (expected: IllegalArgumentException) {
      assertThat(expected.message).isEqualTo(
        "protocols containing h2_prior_knowledge cannot use other protocols: " +
          "[h2_prior_knowledge, h2_prior_knowledge]",
      )
    }
  }

  @Test

    set(value) {
      val protocolList = value.toImmutableList()
      require(Protocol.H2_PRIOR_KNOWLEDGE !in protocolList || protocolList.size == 1) {
        "protocols containing h2_prior_knowledge cannot use other protocols: $protocolList"
      }
      require(Protocol.HTTP_1_1 in protocolList || Protocol.H2_PRIOR_KNOWLEDGE in protocolList) {
        "protocols doesn't contain http/1.1: $protocolList"
      }

      server.protocols = listOf(Protocol.H2_PRIOR_KNOWLEDGE, Protocol.H2_PRIOR_KNOWLEDGE)
      fail<Unit>()
    } catch (expected: IllegalArgumentException) {
      assertThat(expected.message).isEqualTo(
        "protocols containing h2_prior_knowledge cannot use other protocols: " +
          "[h2_prior_knowledge, h2_prior_knowledge]",
      )
    }
  }

  @Test

  private val http2Connection: Http2Connection,
) : ExchangeCodec {
  @Volatile private var stream: Http2Stream? = null

  private val protocol: Protocol =
    if (Protocol.H2_PRIOR_KNOWLEDGE in client.protocols) {
      Protocol.H2_PRIOR_KNOWLEDGE
    } else {
      Protocol.HTTP_2
    }

  @Volatile
  private var canceled = false

  override val isResponseComplete: Boolean
    get() = stream?.isSourceComplete == true

        user.secureConnectEnd(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,

/**
 * Used when we were unsuccessful in the planning phase of a connection:
 *
 *  * A DNS lookup failed
 *  * The configuration is incapable of carrying the request, such as when the client is configured
 *    to use `H2_PRIOR_KNOWLEDGE` but the URL's scheme is `https:`.
 *  * Preemptive proxy authentication failed.
 *
 * Planning failures are not necessarily fatal. For example, even if we can't DNS lookup the first

   *
   * [rfc_2817]: http://www.ietf.org/rfc/rfc2817.txt
   */
  fun requiresTunnel(): Boolean {
    if (proxy.type() != Proxy.Type.HTTP) return false
    return (address.sslSocketFactory != null) ||
      (Protocol.H2_PRIOR_KNOWLEDGE in address.protocols)
  }

  override fun equals(other: Any?): Boolean =
    other is Route &&
      other.address == address &&
      other.proxy == proxy &&
      other.socketAddress == socketAddress