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如何将弹簧座投影与自定义控制器一起使用

spring-rest spring-data spring-boot spring java

Ayoub k · 技术社区 · 6 年前

我有下面的投影,它返回标记的名称:

@Projection(types = NewsTag.class, name = "newsTag")
public interface NewsTagProjection {

    @Value("#{target.tag.name}")
    String getName();
}

我在以下负责newstag模型的存储库中使用它:

@RepositoryRestResource(excerptProjection = NewsTagProjection.class)
public interface NewsTagRepository extends JpaRepository<NewsTag, Integer> {
}

因此,当我调用具有新闻标签列表的新闻库时:

@RepositoryRestResource
public interface NewsRepository extends JpaRepository<News, Integer> {
}

一切正常,它只返回带有NAE的标签列表。
但是,如果我想使用具有相同端点的自定义控制器(比如说,我这样做是为了处理错误),它只返回没有标签列表的新闻,就像投影不存在一样。

这里是控制器:

@RepositoryRestController
@RequestMapping("news")
public class NewsController {

    private NewsService newsService;
    private PagedResourcesAssembler<News> pagedAssembler;
    private NewsResourceAssembler newsResourceAssembler;

    @Autowired
    public void setNewsService(NewsService newsService) {
        this.newsService = newsService;
    }

    @SuppressWarnings("SpringJavaInjectionPointsAutowiringInspection")
    @Autowired
    public void setPagedAssembler(PagedResourcesAssembler<News> pagedAssembler) {
        this.pagedAssembler = pagedAssembler;
    }

    @Autowired
    public void setNewsResourceAssembler(NewsResourceAssembler newsResourceAssembler) {
        this.newsResourceAssembler = newsResourceAssembler;
    }

    // Return all news with pagination
    @GetMapping
    public ResponseEntity<?> getAllNews(Pageable pageable) {
        Page<News> newsPage = this.newsService.getAllNews(pageable);
        return ResponseEntity.ok(this.pagedAssembler.toResource(newsPage, this.newsResourceAssembler));
    }
}

编辑新闻资源汇编程序:

@Service
public class NewsResourceAssembler implements ResourceAssembler<News, Resource<News>> {

    private EntityLinks entityLinks;

    @Autowired
    public void setEntityLinks(EntityLinks entityLinks) {
        this.entityLinks = entityLinks;
    }

    @Override
    public Resource<News> toResource(News news) {
        Link self = entityLinks.linkFor(News.class).slash(news.getId()).withSelfRel();
        Link newsTags = entityLinks.linkFor(News.class).slash(news.getId()).slash("newsTags").withRel("newsTags");
        Link newsComments = entityLinks.linkFor(News.class).slash(news.getId()).slash("newsComments").withRel("newsComments");
        return new Resource<>(news, self, newsTags, newsComments);
    }
}

1 回复 | 直到 6 年前

drowny 6 年前

如果要添加新闻的所有字段,可以操作的返回对象责任。所以我改了这个代码,你能应用到你的代码吗?

NewsResourceAssembler.class 应该是这样的;

@Service
public class NewsResourceAssembler implements ResourceAssembler<News, Resource<NewsResource>> {

    private EntityLinks entityLinks;

    @Autowired
    public void setEntityLinks(EntityLinks entityLinks) {
        this.entityLinks = entityLinks;
    }

    @Override
    public Resource<NewsResource> toResource(News news) {

        Link self = entityLinks.linkFor(News.class).slash(news.getId()).withSelfRel();
        Link newsTags = entityLinks.linkFor(News.class).slash(news.getId()).slash("newsTags").withRel("newsTags");
        Link newsComments = entityLinks.linkFor(News.class).slash(news.getId()).slash("newsComments").withRel("newsComments");

        final NewsResource newsResource = new NewsResource();
        //set any fields to which do you wants to send client
        //newsResource.setExampleFields();
        //newsResource.setNewsTagList(news.getNewsTag()); //example code. Change according to your models

        return new Resource(newsResource, self, newsTags, newsComments);
    }
}

现在你需要 NewsResource.class ,所以应该是这样的;

@JsonIgnoreProperties(ignoreUnknown = true)
public class NewsResource extends ResourceSupport {

    //private fields of which do you wants
    //dont forget list of newstag field
    //ex : private List<NewsTagFields> newsTag = new ArrayList<>();

    //Also should write getter and setter methods
}

附言:别忘了注释行的规则。根据这一变化,您的客户应该分析对客户的传入响应。因为响应时,应该在主对象上更改一些链接rel。但是你的定制参数没有改变。

编辑: 如果在你的 新闻资源.class -->字段 newsTag 应该是这样的( 请不要忘记设置资源汇编程序类中的所有标记! ;

private List<NewsTagFields> newsTag = new ArrayList<>();

现在您需要newstagfields.class。也可以使用这个类;

public class NewsTagFields {

    private final String id;
    private final String name;

    public NewsTagFields(String id, String name) {
        this.id = id;
        this.name = name;
    }

    public String getId() {
        return id;
    }

    public String getName() {
        return name;
    }
}

最后将此代码添加到 ResourceAssembler 添加新的NewstagFields列表; ( 此代码提供获取所有 新闻标签 并转换为列表 新闻标签字段 完全地。并添加到 新闻资源 发送到客户端 )

final List<NewsTagFields> allNewsTag =
                news.getNewsTag().stream()
                        .map(newsTag -> new NewsTagFields(newsTag.getId(), newsTag.getName()))
                        .collect(Collectors.toList());
        newsResource.setNewsTagList(allNewsTag);