Jaxb JAX-RS中的自有资源

我试图理解REST和JAX-RS/JAXB，我与图书馆和书籍有着多对多的关系。我想对图书馆拥有的图书执行GET-POST-PUT-DELETE操作，因此GET的url是“libraries/{library\u id}/books/{book\u id}” 我以这种方式实现了它：

@Stateless
@Path("libraries")
public class LibraryFacadeREST extends AbstractFacade<Library> {

  ...    

   @Path("{library_id}/booksFacade/")
   public BookFacadeREST getBookFacade() {
     return bookFacadeREST;
    }
  ...
}

@Stateless
@Path("books")
public class BookFacadeREST extends AbstractFacade<Book> {
   ...
    @GET
    @Path("{id}")
    @Produces({"application/xml", "application/json"})
    public Book find(@PathParam("id") Long id, @PathParam("library_id") long libraryId) {

       Book book = super.find(id);

       if (libraryId != -1) {
          Library library = em.find(Library.class, libraryId);

          if (book.getLibraries().contains(library)) {
             return book;
          } else {
             return null;
          }
       }

      return null;
   }
   ...
}

@Path("libraries/{library_id}/books")
public class BookFacadeREST extends AbstractFacade<Book> {
    @GET
    @Path("{id}")
    @Produces({"application/xml", "application/json"})
    public Book find(@PathParam("id") Long id, @PathParam("library_id") long libraryId) {
       ...
    }
}

@无状态
@路径（“库”）
公共类LibraryFacadeREST扩展了AbstractFacade{
...    
@路径（“{library\u id}/booksFacade/”）
public BookFacadeREST getBookFacade（）{
返回bookFacadeREST；
}
...
}
@无国籍
@路径（“书籍”）
公共类BookFacadeREST扩展了AbstractFacade{
...
@得到
@路径（“{id}”）
@产生（{“application/xml”、“application/json”}）
公共图书查找（@PathParam（“id”）长id，@PathParam（“library_id”）长libraryId）{
Book Book=super.find（id）；
如果（libraryId！=-1）{
Library Library=em.find（Library.class，libraryId）；
if（book.getLibraries（）.contains（library））{
还书；
}否则{
返回null；
}
}
返回null；
}
...
}

---

但我不喜欢它，它很糟糕，有没有更好的方法来管理JAXR中的自有资源

为什么rest资源需要关系仅仅因为相应的实体有关系？ 我认为图书资源应该这样：

@Stateless
@Path("libraries")
public class LibraryFacadeREST extends AbstractFacade<Library> {

  ...    

   @Path("{library_id}/booksFacade/")
   public BookFacadeREST getBookFacade() {
     return bookFacadeREST;
    }
  ...
}

@Stateless
@Path("books")
public class BookFacadeREST extends AbstractFacade<Book> {
   ...
    @GET
    @Path("{id}")
    @Produces({"application/xml", "application/json"})
    public Book find(@PathParam("id") Long id, @PathParam("library_id") long libraryId) {

       Book book = super.find(id);

       if (libraryId != -1) {
          Library library = em.find(Library.class, libraryId);

          if (book.getLibraries().contains(library)) {
             return book;
          } else {
             return null;
          }
       }

      return null;
   }
   ...
}

@Path("libraries/{library_id}/books")
public class BookFacadeREST extends AbstractFacade<Book> {
    @GET
    @Path("{id}")
    @Produces({"application/xml", "application/json"})
    public Book find(@PathParam("id") Long id, @PathParam("library_id") long libraryId) {
       ...
    }
}

@Path（“libraries/{library\u id}/books”）
公共类BookFacadeREST扩展了AbstractFacade{
@得到
@路径（“{id}”）
@产生（{“application/xml”、“application/json”}）
公共图书查找（@PathParam（“id”）长id，@PathParam（“library_id”）长libraryId）{
...
}
}

是的，我也这么想。通过这种方式，类更具可读性。