code: public String getRFC2253Name(Map<String, String> oidMap) {
          /* check for and return cached name */
          if (oidMap.isEmpty()) {
              if (rfc2253Dn != null) {
                  return rfc2253Dn;
              } else {
                  rfc2253Dn = generateRFC2253DN(oidMap);
                  return rfc2253Dn;
              }
          }
          return generateRFC2253DN(oidMap);
      }
docs: Returns a string form of the X.500 distinguished name
  using the algorithm defined in RFC 2253. Attribute type
  keywords defined in RFC 2253 are emitted, as well as additional
  keywords contained in the OID/keyword map.