docs: public T addPropertiesFile(final Path file) {
          if (file != null) {
              if (Files.notExists(file)) {
                  throw LauncherMessages.MESSAGES.pathDoesNotExist(file);
              }
              if (!Files.isRegularFile(file)) {
                  throw LauncherMessages.MESSAGES.pathNotAFile(file);
              }
              addServerArg("-P", file.toAbsolutePath().normalize().toString());
          }
          return getThis();
      }