public String listMessageCounterHistoryAsHTML() {
    checkStarted();

    clearIO();
    try {
      return MessageCounterHelper.listMessageCounterHistoryAsHTML(new MessageCounter[] {counter});
    } finally {
      blockOnIO();
    }
  }
  public String listMessageCounterHistory() throws Exception {
    checkStarted();

    clearIO();
    try {
      return MessageCounterHelper.listMessageCounterHistory(counter);
    } finally {
      blockOnIO();
    }
  }