code: public DERObject toASN1Object()
      {
          ASN1EncodableVector  v = new ASN1EncodableVector();
  
          v.add(version);
          v.add(holder);
          v.add(issuer);
          v.add(signature);
          v.add(serialNumber);
          v.add(attrCertValidityPeriod);
          v.add(attributes);
  
          if (issuerUniqueID != null)
          {
              v.add(issuerUniqueID);
          }
  
          if (extensions != null)
          {
              v.add(extensions);
          }
  
          return new DERSequence(v);
      }
docs: Produce an object suitable for an ASN1OutputStream.
  <pre>
  AttributeCertificateInfo ::= SEQUENCE {
  version              AttCertVersion -- version is v2,
  holder               Holder,
  issuer               AttCertIssuer,
  signature            AlgorithmIdentifier,
  serialNumber         CertificateSerialNumber,
  attrCertValidityPeriod   AttCertValidityPeriod,
  attributes           SEQUENCE OF Attribute,
  issuerUniqueID       UniqueIdentifier OPTIONAL,
  extensions           Extensions OPTIONAL
  }
  
  AttCertVersion ::= INTEGER { v2(1) }
  </pre>