}

  @Test fun someFallbacksSupported() {
    val sslV3 =
      ConnectionSpec
        .Builder(ConnectionSpec.MODERN_TLS)
        .tlsVersions(TlsVersion.SSL_3_0)
        .build()
    val routePlanner = factory.newRoutePlanner(client)
    val route = factory.newRoute()
    val connectionSpecs = listOf(ConnectionSpec.MODERN_TLS, ConnectionSpec.COMPATIBLE_TLS, sslV3)
    val enabledSocketTlsVersions =
      arrayOf(

  var proxySelector: ProxySelector = RecordingProxySelector()
  var proxyAuthenticator: Authenticator = RecordingOkAuthenticator("password", null)
  var connectionSpecs: List<ConnectionSpec> =
    listOf(
      ConnectionSpec.MODERN_TLS,
      ConnectionSpec.COMPATIBLE_TLS,
      ConnectionSpec.CLEARTEXT,
    )
  var protocols: List<Protocol> =
    listOf(
      Protocol.HTTP_1_1,
    )

        val tlsEquipPlan = planWithCurrentOrInitialConnectionSpec(connectionSpecs, sslSocket)
        val connectionSpec = connectionSpecs[tlsEquipPlan.connectionSpecIndex]

        // Figure out the next connection spec in case we need a retry.
        retryTlsConnection = tlsEquipPlan.nextConnectionSpec(connectionSpecs, sslSocket)

        connectionSpec.apply(sslSocket, isFallback = tlsEquipPlan.isTlsFallback)

   * contains minimally [Protocol.HTTP_1_1].
   */
  @get:JvmName("protocols")
  val protocols: List<Protocol> = protocols.toImmutableList()

  @get:JvmName("connectionSpecs")
  val connectionSpecs: List<ConnectionSpec> =
    connectionSpecs.toImmutableList()

  @JvmName("-deprecated_url")
  @Deprecated(
    message = "moved to val",
    replaceWith = ReplaceWith(expression = "url"),

By default, OkHttp will attempt a `MODERN_TLS` connection.  However by configuring the client connectionSpecs you can allow a fall back to `COMPATIBLE_TLS` connection if the modern configuration fails.

```java
OkHttpClient client = new OkHttpClient.Builder()
    .connectionSpecs(Arrays.asList(ConnectionSpec.MODERN_TLS, ConnectionSpec.COMPATIBLE_TLS))
    .build();
```

      this.x509TrustManagerOrNull = trustManager
    }

    fun connectionSpecs(connectionSpecs: List<ConnectionSpec>) =
      apply {
        if (connectionSpecs != this.connectionSpecs) {
          this.routeDatabase = null
        }

        this.connectionSpecs = connectionSpecs.toImmutableList()
      }

    /**

  }

  @Test @Disabled
  fun connectionSpec() {
    val connectionSpec: ConnectionSpec = ConnectionSpec.RESTRICTED_TLS
    val tlsVersions: List<TlsVersion>? = connectionSpec.tlsVersions()
    val cipherSuites: List<CipherSuite>? = connectionSpec.cipherSuites()
    val supportsTlsExtensions: Boolean = connectionSpec.supportsTlsExtensions()
  }

  @Test @Disabled
  fun cookie() {

    }

    val sessionIds = mutableListOf<String>()

    enableTls()

    val tlsVersion = TlsVersion.forJavaName(tlsVersion)
    val spec =
      ConnectionSpec
        .Builder(ConnectionSpec.MODERN_TLS)
        .tlsVersions(tlsVersion)
        .build()

    var reuseSession = false

    val sslContext = handshakeCertificates.sslContext()

      builder.socketFactory(SSLSocketFactory.getDefault())
    }
  }

  @Test fun noSslSocketFactoryConfigured() {
    val client =
      OkHttpClient
        .Builder()
        .connectionSpecs(listOf(ConnectionSpec.CLEARTEXT))
        .build()
    assertFailsWith<IllegalStateException> {
      client.sslSocketFactory
    }
  }

  @Test fun nullHostileProtocolList() {
    val nullHostileProtocols =

    client =
      client
        .newBuilder()
        .sslSocketFactory(CustomSSLSocketFactory(client.sslSocketFactory), client.x509TrustManager!!)
        .connectionSpecs(
          listOf(
            ConnectionSpec
              .Builder(ConnectionSpec.MODERN_TLS)
              .supportsTlsExtensions(false)
              .build(),
          ),
        ).eventListener(
          object : EventListener() {