code: public String getSingleLineUsage(String name) {
          for (SubCommand<SubCommandDef> cmd : subCommands) {
              if (name.equals(cmd.getName())) {
                  return cmd.getArgumentParser(cmd.newInstance()).getSingleLineUsage();
              }
          }
          throw new ArgumentException("No such " + getName() + " " + name);
      }
docs: Get the single line usage string for a given sub-command.
  
  @param name The sub-command to print help for.
  @return The usage string.