code: String[] getCommandLine() {
          List<String> args = new ArrayList<>();
          if (executable != null) {
              args.add(executable);
          }
          for (int i = 0; i < arguments.size(); i++) {
              CommandArgument argument = arguments.get(i);
              args.add(argument.forCommandLine());
          }
          return args.toArray(new String[args.size()]);
      }
docs: Returns the executable and all defined arguments.