Question

香草实体用户 -

public class User implements Serializable {
    private static final long serialVersionUID = 262950482349139355L;

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;

    @Column(name = "FIRST_NAME", nullable = false, unique = false)
    @Convert(converter = NameConverter.class)
    private String firstName;

    @Column(name = "LAST_NAME", nullable = false, unique = false)
    @Convert(converter = NameConverter.class)
    private String lastName;

    @Column(name = "PHONE_NUM", nullable = false, unique = false)
    @Convert(converter = PhoneNumberConverter.class)
    private String phoneNum;

    @Column(name = "EMAIL", nullable = true, unique = false)
    @Convert(converter = OptionalStringConverter.class)
    private Optional<String> email;
}

在网址中更改主机名的搜索结果 - 2 _links present

{
  "_links" : {
    "self" : {
      "href" : "http://hostname/users/search/findByLastName?lastName=doe{&page,size,sort}",
      "templated" : true
    }
  },
  "_embedded" : {
    "users" : [ {
      "firstName" : "John",
      "lastName" : "Doe",
      "phoneNum" : "111-111-1111",
      "email" : null,
      "_links" : { },
      "_embedded" : { },
      "_links" : {
        "self" : {
          "href" : "http://hostname/users/1",
          "templated" : false
        }
      }
    } ]
  },
  "page" : {
    "size" : 20,
    "totalElements" : 1,
    "totalPages" : 1,
    "number" : 0
  }
}

修改：

当资源被自己访问时，不存在重复链接。但是，当客户端（我的情况下是微服务）使用RestTemplate发出请求时，响应会返回2 _links，如上所示。

@Override
public Collection<Long> getUserIdsByFirstName(String firstName) {
    String findByFirstNameUri = UriComponentsBuilder.fromUriString(userServiceUrl)
        .path("/users/search/findByFirstName").queryParam("firstName", firstName).toUriString();

// This is where ResponseEntity.body would have the 2 _links, if ResponseEntity<String> were used. I used a custom object to weed that out.
ResponseEntity<UserSearchResult> userSearchResult = restTemplate.exchange(findByFirstNameUri, GET, dummyEntity,
        UserSearchResult.class);
     ...
}

我使用的是Spring Data JPA，Spring Data Rest，Spring HATEOAS和Spring Cloud。这是我的Github上的link to the project。

完全披露：我已经在Spring HATEOAS Github上提出了一个问题。

Answer 1

首先，你使用spring-data-rest而不仅仅是spring-hateoas。所以你没有资源，也没有控制器。我认为这是一个主要的误解。

我认为您的自定义存储库出了问题。

我会改变两件事：

从UserRepositoryCustomImpl中删除@Repository
使UserRepository扩展UserRepositoryCustom

所以

public interface UserRepository extends JpaRepository<User, Long>, UserRepositoryCustom

和

public class UserRepositoryCustomImpl implements UserRepositoryCustom

为了实现自定义存储库方法，您需要这样做：

另见http://docs.spring.io/spring-data/data-jpa/docs/current/reference/html/#repositories.custom-implementations

为什么Spring HATEOAS返回重复的链接导致JSON反序列化异常？

1 个答案: