.build();
```

[`HandshakeCertificates`][handshake_certificates] keeps the certificates for a TLS handshake.
Use its [builder][handshake_certificates_builder] to define which certificates the HTTPS server
returns to its clients. The returned instance can create an `SSLSocketFactory` that implements this
policy:

```java
HandshakeCertificates serverCertificates = new HandshakeCertificates.Builder()

        .build()
    val handshakeCertificates =
      HandshakeCertificates
        .Builder()
        .addTrustedCertificate(rootCa.certificate)
        .build()
    val client =
      clientTestRule
        .newClientBuilder()
        .sslSocketFactory(
          handshakeCertificates.sslSocketFactory(),
          handshakeCertificates.trustManager,

    // This client shares a connection pool but has a different SSL socket factory.
    val handshakeCertificates2 = HandshakeCertificates.Builder().build()
    val anotherClient =
      client
        .newBuilder()
        .sslSocketFactory(
          handshakeCertificates2.sslSocketFactory(),
          handshakeCertificates2.trustManager,
        ).build()

      val handshakeCertificates =
        HandshakeCertificates
          .Builder()
          // TODO reenable in official answers
//      .addPlatformTrustedCertificates()
          .addTrustedCertificate(cert)
          .build()

      clientBuilder
        .sslSocketFactory(
          handshakeCertificates.sslSocketFactory(),
          handshakeCertificates.trustManager,
        )
    }

  private fun enableTls() {
    client =
      client
        .newBuilder()
        .sslSocketFactory(
          handshakeCertificates.sslSocketFactory(),
          handshakeCertificates.trustManager,
        ).build()
    server.useHttps(handshakeCertificates.sslSocketFactory())
  }

  private fun assumeNetwork() {
    try {
      InetAddress.getByName("www.google.com")

      ConnectionSpec.COMPATIBLE_TLS,
      ConnectionSpec.CLEARTEXT,
    )
  var protocols: List<Protocol> =
    listOf(
      Protocol.HTTP_1_1,
    )
  var handshakeCertificates: HandshakeCertificates = localhost()
  var sslSocketFactory: SSLSocketFactory? = handshakeCertificates.sslSocketFactory()
  var hostnameVerifier: HostnameVerifier? = HttpsURLConnection.getDefaultHostnameVerifier()
  var uriHost: String = "example.com"
  var uriPort: Int = 1

  private fun enableTls() {
    client =
      client
        .newBuilder()
        .sslSocketFactory(
          handshakeCertificates.sslSocketFactory(),
          handshakeCertificates.trustManager,
        ).hostnameVerifier(RecordingHostnameVerifier())
        .build()
    server.useHttps(handshakeCertificates.sslSocketFactory())
  }

  /** A request body that slowly trickles bytes, expecting to not complete. */

      client
        .newBuilder()
        .protocols(protocols.toList())
        .sslSocketFactory(
          handshakeCertificates.sslSocketFactory(),
          handshakeCertificates.trustManager,
        ).hostnameVerifier(RecordingHostnameVerifier())
        .build()
    server.useHttps(handshakeCertificates.sslSocketFactory())
    server.protocols = protocols.toList()
  }

  private fun upgradeRequest() =
    Request(

  }

  @Test
  fun handshakeCertificates() {
    val handshakeCertificates = HandshakeCertificates.Builder().build()
    val keyManager: X509KeyManager = handshakeCertificates.keyManager
    val trustManager: X509TrustManager = handshakeCertificates.trustManager
    val sslSocketFactory: SSLSocketFactory = handshakeCertificates.sslSocketFactory()

        .body("ABC")
        .build(),
    )
    client =
      client
        .newBuilder()
        .sslSocketFactory(
          handshakeCertificates.sslSocketFactory(),
          handshakeCertificates.trustManager,
        ).hostnameVerifier(NULL_HOSTNAME_VERIFIER)
        .build()
    val request = Request.Builder().url(server.url("/")).build()
    val response1 = client.newCall(request).execute()