code: public String getToken() {
          if (isNull()){
              return NullOidToken;
          }
          StringBuilder res = new StringBuilder();
          res.append(_type.getToken()).append(SEPARATOR).append(_id);
          if (hasMoment()) {
              res.append(SEPARATOR).append(_moment);
          }
          return res.toString();
      }
docs: Get the token for this object identifier
  @return string containing token