java - 将列表对象转换为列表objectDto java的最佳实践

Question

我已经获取了所有数据并将其从 object 转换为 objectDto。但是，不知何故，我觉得我的代码还不好。在这里我需要您的帮助，我需要任何引用/建议来使我的代码更好(在性能方面)。这是我的工作代码:

    @Override
    public List<BookDto> findAll() throws Exception {
        try {
            List<Book> list = bookDao.findAll();
            List<BookDto> listDto = new ArrayList<>();

            for (Book book : list) {
                BookDto bookDto = new BookDto();
                Set<AuthorDto> listAuthorDto = new HashSet<AuthorDto>();
                Set<Author> dataAuthor = new HashSet<Author>();
                book.getAuthor().iterator().forEachRemaining(dataAuthor::add);

                BeanUtils.copyProperties(book, bookDto, "author", "category");
                bookDto.setCategory(book.getCategory().getCategory());

                for (Author author : dataAuthor) {
                    AuthorDto authorDto = new AuthorDto();
                    BeanUtils.copyProperties(author, authorDto);
                    listAuthorDto.add(authorDto);
                }

                bookDto.setAuthor(listAuthorDto);
                listDto.add(bookDto);
            }
            return listDto;
        } catch (Exception e) {
            throw new Exception(e);
        }
    }

这是我需要的输出(已通过上面的代码实现):

[
    {
        "title": "book1",
        "year": "2013",
        "author": [
            {
                "name": "john",
                "address": "NY"
            },
            {
                "name": "angel",
                "address": "LA"
            }
        ],
        "category": "science"
    },
    {
        "title": "book2",
        "year": "2014",
        "author": [
            {
                "name": "john",
                "address": "NY"
            }
        ],
        "category": "science"
    },
    {
        "title": "book3",
        "year": "2009",
        "author": [
            {
                "name": "angel",
                "address": "LA"
            }
        ],
        "category": "comedy"
    }
]

Answer 1

与其重新发明轮子并自己编写它，不如使用现有的库/工具，这是为此而设计的。

我建议使用ModelMapper这是一个很棒的 DTO/实体映射库，您只需要一行即可将实体转换为 DTO，例如:

ModelMapper modelMapper = new ModelMapper();
BookDto bookDTO = modelMapper.map(book, BookDto.class);

您可以查看 library's Examples page或Entity To DTO Conversion for a Spring REST API tutorial更深入地了解这个库。