val sslSocket = doSsl(socket)
        val protocolString = Platform.get().getSelectedProtocol(sslSocket)
        val protocol = if (protocolString != null) get(protocolString) else null
        if (protocol != Protocol.HTTP_2) {
          throw ProtocolException("Protocol $protocol unsupported")
        }
        val connection =
          Http2Connection
            .Builder(false, TaskRunner.INSTANCE)

  override fun secureConnectEnd(handshake: Handshake?) {
    eventListener.secureConnectEnd(call, handshake)
  }

  override fun callConnectEnd(
    route: Route,
    protocol: Protocol?,
  ) {
    eventListener.connectEnd(call, route.socketAddress, route.proxy, protocol)
  }

  override fun connectionConnectEnd(
    connection: Connection,
    route: Route,
  ) {
    poolConnectionListener.connectEnd(connection, route, call)

    assertThat(Protocol.SPDY_3.toString()).isEqualTo("spdy/3.1")
    assertThat(Protocol.HTTP_2.toString()).isEqualTo("h2")
    assertThat(Protocol.H2_PRIOR_KNOWLEDGE.toString())
      .isEqualTo("h2_prior_knowledge")
    assertThat(Protocol.QUIC.toString()).isEqualTo("quic")
    assertThat(Protocol.HTTP_3.toString()).isEqualTo("h3")
  }

import java.net.ProtocolException
import okhttp3.Protocol
import okhttp3.Response
import okio.IOException

/** An HTTP response status line like "HTTP/1.1 200 OK". */
class StatusLine(
  @JvmField val protocol: Protocol,
  @JvmField val code: Int,
  @JvmField val message: String,
) {
  override fun toString(): String =
    buildString {
      if (protocol == Protocol.HTTP_1_0) {
        append("HTTP/1.0")
      } else {

  }

  override fun callConnectEnd(
    route: Route,
    protocol: Protocol?,
  ) {
  }

  override fun connectionConnectEnd(
    connection: Connection,
    route: Route,
  ) {
  }

  override fun connectFailed(
    route: Route,
    protocol: Protocol?,
    e: IOException,
  ) {
  }

  override fun connectionAcquired(connection: Connection) {
  }

import okhttp3.CallEvent.ResponseFailed
import okhttp3.DelegatingServerSocketFactory
import okhttp3.DelegatingSocketFactory
import okhttp3.MediaType
import okhttp3.OkHttpClient
import okhttp3.OkHttpClientTestRule
import okhttp3.Protocol.HTTP_1_1
import okhttp3.RecordingEventListener
import okhttp3.Request
import okhttp3.RequestBody
import okhttp3.SimpleProvider
import okhttp3.internal.http.CancelTest.CancelMode.CANCEL

 * Prevent leaking a cache item's InputStreams when metadata read fails.
 * Use a string to identify TLS versions in routes.
 * Add frame logger for HTTP/2.
 * Replacing `httpMinorVersion` with `Protocol`. Expose HTTP/1.0 as a potential protocol.
 * Use `Protocol` to describe framing.
 * Implement write timeouts for HTTP/1.1 streams.
 * Avoid use of SPDY stream ID 1, as that's typically used for UPGRADE.
 * Support OAuth in `Authenticator`.

    val response = client.newCall(request).execute()

    response.use {
      assertEquals(200, response.code)
      assertEquals(TlsVersion.TLS_1_3, response.handshake?.tlsVersion)
      assertEquals(Protocol.HTTP_2, response.protocol)

      assertThat(response.exchangeAccessor!!.connectionAccessor.socket())
        .isInstanceOf<SSLSocketImpl>()
    }
  }

  @Test
  fun testSupportedProtocols() {

        .url("https://google.com/robots.txt")
        .build();
    try (Response response = client.newCall(request).execute()) {
      assertEquals(200, response.code());
      assertEquals(Protocol.HTTP_2, response.protocol());
    }
  }

            .url(url)
            .build();
    try (Response response = client.newCall(request).execute()) {
      assertTrue(response.code() == 200 || response.code() == 404);
      assertEquals(Protocol.HTTP_2, response.protocol());

      for (Certificate c: response.handshake().peerCertificates()) {
        X509Certificate x = (X509Certificate) c;
        System.out.println(x.getSubjectDN());
      }
    }
  }