code: public static SettingsPopulation get(Map<String, String[]> clArgs, SettingsCommand command)
      {
          // set default size to number of commands requested, unless set to err convergence, then use 1M
          String defaultLimit = command.count <= 0 ? "1000000" : Long.toString(command.count);
  
          String[] params = clArgs.remove("-pop");
          if (params == null)
          {
              if (command instanceof SettingsCommandUser && ((SettingsCommandUser)command).hasInsertOnly())
              {
                  return new SettingsPopulation(new SequentialOptions(defaultLimit));
              }
  
              // return defaults:
              switch(command.type)
              {
                  case WRITE:
                  case COUNTER_WRITE:
                      return new SettingsPopulation(new SequentialOptions(defaultLimit));
                  default:
                      return new SettingsPopulation(new DistributionOptions(defaultLimit));
              }
          }
          GroupedOptions options = GroupedOptions.select(params, new SequentialOptions(defaultLimit), new DistributionOptions(defaultLimit));
          if (options == null)
          {
              printHelp();
              System.out.println("Invalid -pop options provided, see output for valid options");
              System.exit(1);
          }
          return options instanceof SequentialOptions ?
                  new SettingsPopulation((SequentialOptions) options) :
                  new SettingsPopulation((DistributionOptions) options);
      }
docs: CLI Utility Methods