}

    @Test
    @DisplayName("Should handle null protocol ID")
    void testNullProtocolId() {
        // Protocol ID is a constant in transform header, not settable
        // This test is not applicable - the protocol ID is always TRANSFORM_PROTOCOL_ID
        assertTrue(true);
    }

    @Test
    @DisplayName("Should handle invalid protocol ID length")

        synchronized (PROTOCOL_HANDLERS) {
            URLStreamHandler handler = PROTOCOL_HANDLERS.get(protocol);
            if (handler != null) {
                return handler;
            }
            if (factory != null) {
                handler = factory.createURLStreamHandler(protocol);
            }
            if (handler == null) {

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

        // Protocol errors
        INVALID_PARAMETER("Invalid parameter", ErrorCategory.PROTOCOL, false), NOT_SUPPORTED("Operation not supported",
                ErrorCategory.PROTOCOL, false), INVALID_PROTOCOL("Invalid protocol", ErrorCategory.PROTOCOL,
                        false), MESSAGE_TOO_LARGE("Message too large", ErrorCategory.PROTOCOL, false),

        // Resource errors

            .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());
      }
    }
  }

      assertThat(it.protocol).isEqualTo(Protocol.HTTP_2)
      assertThat(it.handshake!!.tlsVersion).isEqualTo(TlsVersion.TLS_1_3)
    }
  }

  @Test
  @Disabled
  fun testGoogle() {
    assumeNetwork()

    val request = Request.Builder().url("https://google.com/robots.txt").build()

    client.newCall(request).execute().use {
      assertThat(it.protocol).isEqualTo(Protocol.HTTP_2)

    server.setProtocols(Collections.singletonList(Protocol.H2_PRIOR_KNOWLEDGE));
    server.enqueue(new MockResponse().setBody("hello"));
    server.start();

    OkHttpClient client = new OkHttpClient.Builder()
        .socketFactory(new UnixDomainSocketFactory(socketFile))
        .protocols(Collections.singletonList(Protocol.H2_PRIOR_KNOWLEDGE))
        .build();

    Request request = new Request.Builder()

    }

    @Override public void connectEnd(
        Call call, InetSocketAddress inetSocketAddress, Proxy proxy, Protocol protocol) {
      printEvent("connectEnd");
    }

    @Override public void connectFailed(Call call, InetSocketAddress inetSocketAddress, Proxy proxy,
        Protocol protocol, IOException ioe) {
      printEvent("connectFailed");
    }

            return "[" + compressed + "]";
        }
        return address.getHostAddress();
    }

    /**
     * Builds a URL from protocol, InetAddress, port, and path.
     * Properly handles IPv6 addresses by wrapping them in brackets.
     *
     * @param protocol the protocol (e.g., "http", "https")
     * @param address the InetAddress for the host
     * @param port the port number

   * HTTPS.
   */
  fun handshake(): Handshake?

  /**
   * Returns the protocol negotiated by this connection, or [Protocol.HTTP_1_1] if no protocol
   * has been negotiated. This method returns [Protocol.HTTP_1_1] even if the remote peer is using
   * [Protocol.HTTP_1_0].
   */
  fun protocol(): Protocol