docs: protected static String[] splitTokens(String command) {
      if (command.length() == 0) {
        throw new IllegalArgumentException("Empty command");
      }
  
      StringTokenizer st = new StringTokenizer(command);
      String[] cmdarray = new String[st.countTokens()];
      for (int i = 0; st.hasMoreTokens(); i++) {
        cmdarray[i] = st.nextToken();
      }
      return cmdarray;
    }