code: private static void AddIdentifierToList(CommPortIdentifier cpi) {
          LOGGER.fine("CommPortIdentifier:AddIdentifierToList()");
          synchronized (Sync) {
              if (CommPortIndex == null) {
                  CommPortIndex = cpi;
                  LOGGER.fine("CommPortIdentifier:AddIdentifierToList() null");
              } else {
                  CommPortIdentifier index = CommPortIndex;
                  while (index.next != null) {
                      index = index.next;
                      LOGGER.fine("CommPortIdentifier:AddIdentifierToList() index.next");
                  }
                  index.next = cpi;
              }
          }
      }
docs: by implementing its own linked list functionallity