if (!isAlpnBootEnabled()) {
            System.err.println("Warning: ALPN Boot not enabled")
          }
        } else if (platformSystemProperty == JDK8_PROPERTY) {
          if (isAlpnBootEnabled()) {
            System.err.println("Warning: ALPN Boot enabled unintentionally")
          }

 *  Fix: Cache 302s and 308s that include appropriate response headers.
 *  Fix: Improve pooling of connections that use proxy selectors.
 *  Fix: Don't leak connections when using ALPN on the desktop.
 *  Fix: Update Jetty ALPN to `7.1.2.v20141202` (Java 7) and `8.1.2.v20141202` (Java 8).
    This fixes a bug in resumed TLS sessions where the wrong protocol could be
    selected.

import org.codehaus.mojo.animal_sniffer.IgnoreJRERequirement

/**
 * Access to platform-specific features.
 *
 * ### Session Tickets
 *
 * Supported on Android 2.3+.
 * Supported on JDK 8+ via Conscrypt.
 *
 * ### ALPN (Application Layer Protocol Negotiation)
 *
 * Supported on Android 5.0+.
 *
 * Supported on OpenJDK 8 via the JettyALPN-boot library or Conscrypt.
 *
 * Supported on OpenJDK 9+ via SSLParameters and SSLSocket features.

     *     represented as a combination of scheme, host and port. When empty, the origin is that of
     *     the `streamId`.
     * @param protocol an ALPN protocol, such as `h2`.
     * @param host an IP address or hostname.
     * @param port the IP port associated with the service.
     * @param maxAge time in seconds that this alternative is considered fresh.
     */

    val response = call.execute()
    assertThat(response.body.string()).isEqualTo("success")
  }

  /**
   * Tests that use this will fail unless boot classpath is set. Ex. `-Xbootclasspath/p:/tmp/alpn-boot-8.0.0.v20140317`
   */
  private fun enableProtocol(protocol: Protocol) {
    enableTls()
    client =
      client.newBuilder()
        .protocols(listOf(protocol, Protocol.HTTP_1_1))
        .build()

_2022-06-12_

 *  Upgrade: [Kotlin 1.6.20][kotlin_1_6_20].
 *  Upgrade: [Okio 3.0.0][okio_3_0_0].
 *  Fix: Recover gracefully when Android's `NativeCrypto` crashes with `"ssl == null"`. This occurs
    when OkHttp retrieves ALPN state on a closed connection.


## Version 4.9.3

_2021-11-21_

 *  Fix: Don't fail HTTP/2 responses if they complete before a `RST_STREAM` is sent.


## Version 4.9.2

_2021-09-30_

    }

  /**
   * True if ALPN is used on incoming HTTPS connections to negotiate a protocol like HTTP/1.1 or
   * HTTP/2. This is true by default; set to false to disable negotiation and restrict connections
   * to HTTP/1.1.
   */
  var protocolNegotiationEnabled: Boolean = true

  /**
   * The protocols supported by ALPN on incoming HTTPS connections in order of preference. The list

      certificatePinner.check(address.url.host) {
        handshake.peerCertificates.map { it as X509Certificate }
      }

      // Success! Save the handshake and the ALPN protocol.
      val maybeProtocol =
        if (connectionSpec.supportsTlsExtensions) {
          Platform.get().getSelectedProtocol(sslSocket)
        } else {
          null
        }
      socket = sslSocket

    5.x upgrade as an opportunity to remove very obsolete APIs.
 *  Fix: Recover gracefully when Android's `NativeCrypto` crashes with `"ssl == null"`. This occurs
    when OkHttp retrieves ALPN state on a closed connection.
 *  Upgrade: [Kotlin 1.6.21][kotlin_1_6_21].
 *  Upgrade: [Okio 3.1.0][okio_3_1_0].


## Version 5.0.0-alpha.6

_2022-03-14_