PreferencesFxUtils { public static List<Category> flattenCategories(List<Category> categoryLst) { if (categoryLst == null) { return null; } List<Category> flatCategoryLst = new ArrayList<>(); flattenCategories(flatCategoryLst, categoryLst); return flatCategoryLst; }  static List<Setting> categoriesToSettings(List<Category> categories); static List<Element> categoriesToElements(List<Category> categories); static HashMap<Setting, Category> mapSettingsToCategories(List<Category> categories); static HashMap<Group, Category> mapGroupsToCategories(List<Category> categories); static List<Category> filterCategoriesByDescription(List<Category> categories,
                                                             String description); static List<Setting> filterSettingsByDescription(List<Setting> settings,
                                                          String description); static List<Setting> groupsToSettings(List<Group> groups); static List<Group> filterGroupsByDescription(List<Group> groups, String description); static List<Group> categoriesToGroups(List<Category> categories); static int getRowCount(GridPane gridPane); static List<Category> flattenCategories(List<Category> categoryLst);  }
@Test public void flattenCategories() { }