val rootCa =
      HeldCertificate
        .Builder()
        .serialNumber(1L)
        .certificateAuthority(1)
        .commonName("root")
        .build()
    val intermediateCa =
      HeldCertificate
        .Builder()
        .signedBy(rootCa)
        .certificateAuthority(0)
        .serialNumber(2L)
        .commonName("intermediate_ca")
        .build()
    val certificate =

      HeldCertificate
        .Builder()
        .serialNumber(1L)
        .certificateAuthority(1)
        .commonName("root")
        .addSubjectAlternativeName("root_ca.com")
        .build()
    serverIntermediateCa =
      HeldCertificate
        .Builder()
        .signedBy(serverRootCa)
        .certificateAuthority(0)
        .serialNumber(2L)
        .commonName("intermediate_ca")

    fun serialNumber(serialNumber: BigInteger) =
      apply {
        this.serialNumber = serialNumber
      }

    /** Sets this certificate's serial number. If unset the serial number will be 1. */
    fun serialNumber(serialNumber: Long) =
      apply {
        serialNumber(BigInteger.valueOf(serialNumber))
      }

    /**

          subjectPublicKey = it[1] as BitString,
        )
      },
    )

  /**
   * ```
   * TBSCertificate ::= SEQUENCE  {
   *   version         [0]  EXPLICIT Version DEFAULT v1,
   *   serialNumber         CertificateSerialNumber,
   *   signature            AlgorithmIdentifier,
   *   issuer               Name,
   *   validity             Validity,
   *   subject              Name,

    builder = builder.addSubjectAlternativeName("")
    builder = builder.commonName("")
    builder = builder.organizationalUnit("")
    builder = builder.serialNumber(BigInteger.ZERO)
    builder = builder.serialNumber(0L)
    builder = builder.keyPair(keyPair)
    builder = builder.keyPair(keyPair.public, keyPair.private)
    builder = builder.signedBy(HeldCertificate.Builder().build())

      val result: MutableList<String> = ArrayList()
      for (certificate in certificates) {
        result.add(certificate.subjectDN.toString() + " " + certificate.serialNumber)
      }
      return result.toString()
    }
  }

  /**
   * Tests that use this will fail unless boot classpath is set. Ex. `-Xbootclasspath/p:/tmp/alpn-boot-8.0.0.v20140317`
   */