.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()

    }
  }

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

/**
 * This single Junit 4 test is our Android test suite on API 21-25.
 */
class SingleAndroidTest {
  private val handshakeCertificates = localhost()

  private var client: OkHttpClient =
    OkHttpClient
      .Builder()
      .sslSocketFactory(
        handshakeCertificates.sslSocketFactory(),
        handshakeCertificates.trustManager,
      ).connectionPool(ConnectionPool(0, 1, TimeUnit.SECONDS))
      .build()

  val hostname = "local.host"
  private val handshakeCertificates =
    run {
      // Generate a self-signed cert for the server to serve and the client to trust.
      val heldCertificate =
        HeldCertificate
          .Builder()
          .commonName(hostname)
          .addSubjectAlternativeName(hostname)
          .build()
      HandshakeCertificates
        .Builder()
        .heldCertificate(heldCertificate)

        .build()
    val handshakeCertificates =
      HandshakeCertificates
        .Builder()
        .heldCertificate(heldCertificate)
        .addTrustedCertificate(heldCertificate.certificate)
        .build()

    // Use that certificate on the server and trust it on the client.
    server.useHttps(handshakeCertificates.sslSocketFactory())
    client =
      client

      client
        .newBuilder()
        .sslSocketFactory(
          handshakeCertificates.sslSocketFactory(),
          handshakeCertificates.trustManager,
        ).hostnameVerifier(RecordingHostnameVerifier())
        .build()
    server1.useHttps(handshakeCertificates.sslSocketFactory())
    server2.useHttps(handshakeCertificates.sslSocketFactory())
  }

  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")

  }

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

      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. */