this one.
 *  New: Include suppressed exceptions when all routes to a target service fail.


## Version 4.4.1

_2020-03-08_

 *  Fix: Don't reuse a connection on redirect if certs match but DNS does not. For better
    locality and performance OkHttp attempts to use the same pooled connection across redirects and
    follow-ups. It independently shares connections when the IP addresses and certificates match,

  /** The low-level TCP socket. */
  private var rawSocket: Socket?,
  /**
   * The application layer socket. Either an [SSLSocket] layered over [rawSocket], or [rawSocket]
   * itself if this connection does not use SSL.
   */
  private var socket: Socket?,
  private var handshake: Handshake?,
  private var protocol: Protocol?,
  private var source: BufferedSource?,
  private var sink: BufferedSink?,

      }

    /**
     * Sets the socket factory used to secure HTTPS connections. If unset, the system default will
     * be used.
     *
     * @deprecated [SSLSocketFactory] does not expose its [X509TrustManager], which is a field that
     *     OkHttp needs to build a clean certificate chain. This method instead must use reflection
     *     to extract the trust manager. Applications should prefer to call

        return userResponse.request
      }

      else -> return null
    }
  }

  private fun buildRedirectRequest(
    userResponse: Response,
    method: String,
  ): Request? {
    // Does the client allow redirects?
    if (!client.followRedirects) return null

    val location = userResponse.header("Location") ?: return null
    // Don't follow redirects to unsupported protocols.

   * written in the order they were enqueued.
   *
   * If a frame cannot be sent - because there are none enqueued or because the web socket is not
   * connected - this does nothing and returns false. Otherwise this returns true and the caller
   * should immediately invoke this method again until it returns false.
   *

   * the cookie from being accessible to scripts.
   */
  @get:JvmName("httpOnly") val httpOnly: Boolean,
  /**
   * Returns true if this cookie does not expire at the end of the current session.
   *
   * This is true if either 'expires' or 'max-age' is present.
   */
  @get:JvmName("persistent") val persistent: Boolean,
  /**

    prepared to build a TLS API for Kotlin/Native.

    We'd prefer a multiplatform HTTP client API that's backed by OkHttp on Android and JVM, and
    other engines on other platforms. [Ktor] does this pretty well today!

 *  Breaking: Use `kotlin.time.Duration` in APIs like `OkHttpClient.Builder.callTimeout()`. This
    update also drops support for the `DurationUnit` functions introduced in earlier alpha releases

    /**
     * Handle a new stream from this connection's peer. Implementations should respond by either
     * [replying to the stream][Http2Stream.writeHeaders] or [closing it][Http2Stream.close]. This
     * response does not need to be synchronous.
     *
     * Multiple calls to this method may be made concurrently.
     */
    @Throws(IOException::class)
    abstract fun onStream(stream: Http2Stream)

    /**

 *
 * [ietf_alpn]: http://tools.ietf.org/html/draft-ietf-tls-applayerprotoneg
 */
enum class Protocol(private val protocol: String) {
  /**
   * An obsolete plaintext framing that does not use persistent sockets by default.
   */
  HTTP_1_0("http/1.0"),

  /**
   * A plaintext framing that includes persistent connections.
   *

    Thread.sleep(TimeUnit.NANOSECONDS.toMillis(Http2Connection.DEGRADED_PONG_TIMEOUT_NS.toLong()))
    assertThat(connection.isHealthy(System.nanoTime())).isFalse()

    // When a pong does arrive, the connection becomes healthy again.
    connection.writePingAndAwaitPong()
    assertThat(connection.isHealthy(System.nanoTime())).isTrue()

    // Verify the peer received what was expected.