* See the License for the specific language governing permissions and
 * limitations under the License.
 */
package okhttp3

import okio.IOException

/**
 * Protocols that OkHttp implements for [ALPN][ietf_alpn] selection.
 *
 * ## Protocol vs Scheme
 *
 * Despite its name, [java.net.URL.getProtocol] returns the [scheme][java.net.URI.getScheme] (http,

      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
        }

problems. If your service has multiple IP addresses, OkHttp will attempt alternate addresses if the
first connect fails. This is necessary for IPv4+IPv6 and services hosted in redundant data
centers. OkHttp supports modern TLS features (TLS 1.3, ALPN, certificate pinning). It can be
configured to fall back for broad connectivity.

Using OkHttp is easy. Its request/response API is designed with fluent builders and immutability. It

     *
     * Other TLS features are still used but provide no security benefits in absence of the above
     * gaps. For example, an insecure TLS connection is capable of negotiating HTTP/2 with ALPN and
     * it also has a regular-looking handshake.
     *
     * **This feature is not supported on Android API levels less than 24.** Prior releases lacked
     * a mechanism to trust some hosts and not others.
     *

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.

        implementation(libs.junit.vintage.engine)

        implementation(libs.robolectric)
      }
    }
  }
}

if (platform == "jdk8alpn") {
  // Add alpn-boot on Java 8 so we can use HTTP/2 without a stable API.
  val alpnBootVersion = alpnBootVersion()
  if (alpnBootVersion != null) {
    val alpnBootJar = configurations.detachedConfiguration(

  /**
   * 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.
   */
  public var protocolNegotiationEnabled: Boolean = true

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

     *
     * If multiple protocols are specified, [ALPN][alpn] will be used to negotiate a transport.
     * Protocol negotiation is only attempted for HTTPS URLs.
     *
     * [Protocol.HTTP_1_0] is not supported in this set. Requests are initiated with `HTTP/1.1`. If
     * the server responds with `HTTP/1.0`, that will be exposed by [Response.protocol].
     *
     * [alpn]: http://tools.ietf.org/html/draft-ietf-tls-applayerprotoneg

    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))

    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_