code: public CommandGroup getCommandGroup(String groupId) {
          
          if (logger.isDebugEnabled()) {
              logger.debug("Attempting to retrieve command group with id ["
                           + groupId
                           + "] from the command registry.");
          }
          
          Object command = getCommand(groupId, CommandGroup.class);
          
          return (CommandGroup) command;
          
      }
docs: {@inheritDoc}
  @deprecated