public synchronized void add(OptionGroup group)
public synchronized void add(Option opt)
  public synchronized void add(OptionGroup group)  {    options.addAll(group.options);    // This ensures that the final group always appears at the end    // of the options.    if (optionGroups.isEmpty())      optionGroups.add(group);    else      optionGroups.add(optionGroups.size() - 1, group);  }