HATEOAS RESTFull实体关系破裂

时间:2014-08-05 15:53:35

标签: spring rest jpa hateoas

我有一个非常基本的系统使用Spring和HATEOAS,我发现了一个问题。我有两个非常基本的实体汽车和一个人。避免吸气者和闯入者使问题更具可读性。

@Entity
public class Car implements Serializable{
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private long carId;
    @ManyToOne(fetch=FetchType.LAZY)
    @JoinColumn(name="personId")
    private Person owner;
    private String color;
    private String brand;
}

@Entity
public class Person implements Serializable {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private long personId;
    private String firstName;
    private String lastName;
    @OneToMany(mappedBy="owner")
    private List<Car> cars;
}

这是我的存储库:

@RepositoryRestResource(collectionResourceRel = "people", path = "people")
public interface PersonRepository extends PagingAndSortingRepository<Person, Long> {
    List<Person> findByLastName(@Param("name") String name);
}

@RepositoryRestResource(collectionResourceRel = "cars", path = "cars")
public interface CarRepository extends PagingAndSortingRepository<Car, Long> {
    List<Person> findByBrand(@Param("brand") String name);
}

我可以创建和查询它们,但有些引用链接已被破坏。例如,一些POST成功创建了两个相关实体:

http://localhost:8080/people
{  "firstName" : "Frodo",  "lastName" : "Baggins"}

http://localhost:8080/cars
{ "color":"black","brand":"volvo", "owner":"http://localhost:8080/people/1"}

这是对他们的GET回复:

http://localhost:8080/cars/2

 {
    color: "black2",
    brand: "volvo2",
    _links: {
       self: {
           href: "http://localhost:8080/cars/2"
       },
       owner: {
           href: "http://localhost:8080/cars/2/owner"
       }
    }
 }

http://localhost:8080/people/1

{
   firstName: "Frodo",
   lastName: "Baggins",
   _links: {
      self: {
         href: "http://localhost:8080/people/1"
      },
      cars: {
         href: "http://localhost:8080/people/1/cars"
      }
   }
}

但我不知道为什么车主在车上有这个网址:

http://localhost:8080/cars/2/owner

实际上不起作用。

对此有何帮助?

1 个答案:

答案 0 :(得分:1)

它就在那里,因为这就是HATEOAS的意义所在,用链接表示实体/资源关系。

我不确定为什么它不起作用。我猜它可能不起作用,因为在检索汽车资源时并不急切地获取所有者。

您可以按照https://stackoverflow.com/a/24660635/442773

中的步骤自定义生成的链接