### Question:
CategoryService { public CategoryDto findCategoryById(String categoryId) { return categoryDao.findById(categoryId) .map(categoryMapper::toDto) .orElseThrow(ResourceNotFoundException::new); } CategoryService(CategoryDao categoryDao, ArticleDao articleDao, CategoryMapper categoryMapper); Page<CategoryDto> findCategoryByCondition(CategoryDto categoryDto, Pageable pageable); CategoryDto findCategoryById(String categoryId); void saveOrUpdate(CategoryDto categoryDto); void deleteCategoryByIds(List<String> categoryIds);  }### Answer:
@Test void testFindCategoryById() { CategoryDto result = categoryService.findCategoryById("categoryId"); Assertions.assertEquals(new CategoryDto(), result); }