code: @Override
      public DERObject toASN1Object()
      {
          ASN1EncodableVector v = new ASN1EncodableVector();
  
          v.add(issuer);
          v.add(serial);
  
          if (issuerUID != null)
          {
              v.add(issuerUID);
          }
  
          return new DERSequence(v);
      }
docs: Produce an object suitable for an ASN1OutputStream.
  <pre>
  IssuerSerial ::= SEQUENCE {
  issuer GeneralNames,
  serial CertificateSerialNumber,
  issuerUID UniqueIdentifier OPTIONAL
  }
  </pre>