code: DerValue findAttribute(ObjectIdentifier oid) {
          for (int i = 0; i < assertion.length; i++) {
              if (assertion[i].oid.equals((Object)oid)) {
                  return assertion[i].value;
              }
          }
          return null;
      }
docs: /*
  return specified attribute value from RDN
  
  @params oid ObjectIdentifier of attribute to be found
  @returns DerValue of attribute value; null if attribute does not exist