docs: protected String getSeparatorPlusAffinityToken(String sessId) {
          StringBuffer separatorPlusAffToken = new StringBuffer();
          String affToken = _store.getAffinityToken(sessId, _sessCtx.getAppName());
          if (affToken == null) { // store has not overridden token impl
              affToken = _cloneID;
          }
          if (affToken != null && affToken.length() > 0) {
              separatorPlusAffToken.append(SessionManagerConfig.getCloneSeparator()).append(affToken);
          }
          return separatorPlusAffToken.toString();
      }