* The pool will routinely try to pre-emptively open connections to satisfy this minimum.
     * Connections will still be closed if they idle beyond the keep-alive but will be replaced.
     */
    @JvmField val minimumConcurrentCalls: Int = 0,
    /** How long to wait to retry pre-emptive connection attempts that fail. */
    @JvmField val backoffDelayMillis: Long = 60 * 1000,

     * found, the existing values are replaced.
     */
    operator fun set(
      name: String,
      value: Date,
    ) = set(name, value.toHttpDateString())

    /**
     * Set a field with the specified instant. If the field is not found, it is added. If the field
     * is found, the existing values are replaced.
     */

        when {
          startsWith('"'.code.toByte()) -> readQuotedString()
          else -> readToken()
        } ?: return // Expected a value.

      val replaced = parameters.put(peek, parameterValue)
      peek = null
      if (replaced != null) return // Unexpected duplicate parameter.
      if (!skipCommasAndWhitespace() && !exhausted()) return // Expected ',' or EOF.
    }

need to customize SSL, do so for your specific OkHttpClient instance only.

##### Synthetic headers have changed

Previously OkHttp added a synthetic response header, `OkHttp-Selected-Transport`. It
has been replaced with a new synthetic header, `OkHttp-Selected-Protocol`.

##### Changes

 * New: Support for `HTTP-draft-09/2.0`.
 * New: Support for `spdy/3.1`. Dropped support for `spdy/3`.

        i -= 2
      }
      i += 2
    }
  }

/**
 * Set a field with the specified value. If the field is not found, it is added. If the field is
 * found, the existing values are replaced.
 */
internal fun Headers.Builder.commonSet(
  name: String,
  value: String,
) = apply {
  headersCheckName(name)
  headersCheckValue(value, name)
  removeAll(name)
  commonAddLenient(name, value)

    // Connections are created as soon as a policy is set
    setPolicy(pool, address, ConnectionPool.AddressPolicy(2))
    assertThat(pool.connectionCount()).isEqualTo(2)

    // Connections are replaced if they idle out or are evicted from the pool
    evictAllConnections(pool)
    assertThat(pool.connectionCount()).isEqualTo(2)
    forceConnectionsToExpire(pool, expireTime)

     */
    open fun url(url: URL) = url(url.toString().toHttpUrl())

    /**
     * Sets the header named [name] to [value]. If this request already has any headers
     * with that name, they are all replaced.
     */
    open fun header(
      name: String,
      value: String,
    ) = commonHeader(name, value)

    /**
     * Adds a header with [name] and [value]. Prefer this method for multiply-valued

        append(":")
        for (pin in pins) {
          append("\n    ")
          append(pin)
        }
      }
    throw SSLPeerUnverifiedException(message)
  }

  @Deprecated(
    "replaced with {@link #check(String, List)}.",
    ReplaceWith("check(hostname, peerCertificates.toList())"),
  )
  @Throws(SSLPeerUnverifiedException::class)
  fun check(
    hostname: String,

      apply {
        this.handshake = handshake
      }

    /**
     * Sets the header named [name] to [value]. If this request already has any headers
     * with that name, they are all replaced.
     */
    open fun header(
      name: String,
      value: String,
    ) = commonHeader(name, value)

    /**
     * Adds a header with [name] to [value]. Prefer this method for multiply-valued

        altNames += altName
      }

    /**
     * Set this certificate's common name (CN). Historically this held the hostname of TLS
     * certificate, but that practice was deprecated by [RFC 2818][rfc_2818] and replaced with
     * [addSubjectAlternativeName]. If unset a random string will be used.
     *
     * [rfc_2818]: https://tools.ietf.org/html/rfc2818
     */
    fun commonName(cn: String) =
      apply {