val data = CertificateAdapters.certificate.toDer(this)
    try {
      val certificateFactory = CertificateFactory.getInstance("X.509")
      val certificates = certificateFactory.generateCertificates(Buffer().write(data).inputStream())
      return certificates.single() as X509Certificate
    } catch (e: NoSuchElementException) {
      throw IllegalArgumentException("failed to decode certificate", e)
    } catch (e: IllegalArgumentException) {

        .serialNumber(1L)
        .build()
    val rootB =
      HeldCertificate
        .Builder()
        .serialNumber(2L)
        .build()
    assertThat(get(rootB.certificate, rootA.certificate))
      .isEqualTo(get(rootA.certificate, rootB.certificate))
  }

  @Test
  fun equalsFromTrustManager() {
    val handshakeCertificates = HandshakeCertificates.Builder().build()

    .heldCertificate(serverCertificate, intermediateCertificate.certificate())
    .build();
```

The client only needs to know the trusted root certificate. It checks the server's certificate by
validating the signatures within the chain.

```java
HandshakeCertificates clientCertificates = new HandshakeCertificates.Builder()
    .addTrustedCertificate(rootCertificate.certificate())
    .build();

 *
 *  * The server's handshake certificates must have a [held certificate][HeldCertificate] (a
 *    certificate and its private key). The certificate's subject alternative names must match the
 *    server's hostname. The server must also have is a (possibly-empty) chain of intermediate
 *    certificates to establish trust from a root certificate to the server's certificate. The root
 *    certificate is not included in this chain.

      }
    }

  fun verify(
    host: String,
    certificate: X509Certificate,
  ): Boolean =
    when {
      host.canParseAsIpAddress() -> verifyIpAddress(host, certificate)
      else -> verifyHostname(host, certificate)
    }

  /** Returns true if [certificate] matches [ipAddress]. */
  private fun verifyIpAddress(
    ipAddress: String,
    certificate: X509Certificate,
  ): Boolean {

        peerCertificates = listOf(serverCertificate.certificate, serverIntermediate.certificate),
        localCertificates = listOf(),
      )

    assertThat(handshake.tlsVersion).isEqualTo(TlsVersion.TLS_1_3)
    assertThat(handshake.cipherSuite).isEqualTo(CipherSuite.TLS_AES_128_GCM_SHA256)
    assertThat(handshake.peerCertificates).containsExactly(
      serverCertificate.certificate,
      serverIntermediate.certificate,
    )

 * certificate is signed by the certificate that follows, and the last certificate is a trusted CA
 * certificate.
 *
 * Use of the chain cleaner is necessary to omit unexpected certificates that aren't relevant to
 * the TLS handshake and to extract the trusted CA certificate for the benefit of certificate
 * pinning.
 */
abstract class CertificateChainCleaner {
  @Throws(SSLPeerUnverifiedException::class)

    throw IllegalArgumentException("failed to decode certificate", nsee)
  } catch (iae: IllegalArgumentException) {
    throw IllegalArgumentException("failed to decode certificate", iae)
  } catch (e: GeneralSecurityException) {
    throw IllegalArgumentException("failed to decode certificate", e)
  }
}

/**
 * Returns the certificate encoded in [PEM format][rfc_7468].
 *

    assertThat(listOf(clientCertificate.certificate, clientIntermediate.certificate))
      .isEqualTo(serverHandshake.peerCertificates)
    assertThat(listOf(serverCertificate.certificate, serverIntermediate.certificate))
      .isEqualTo(serverHandshake.localCertificates)
    val clientHandshake = clientHandshakeFuture.get()
    assertThat(listOf(serverCertificate.certificate, serverIntermediate.certificate))

   * This is unexpected unless the trust root index in this class has a different trust manager than
   * what was used to establish [chain].
   */
  @Throws(SSLPeerUnverifiedException::class)
  override fun clean(
    chain: List<Certificate>,
    hostname: String,
  ): List<Certificate> {
    val queue: Deque<Certificate> = ArrayDeque(chain)