POST POST新实体时如何在Spring Data REST中引用具有继承的实体?
我有加入继承的实体:
支持者
@Entity
@Inheritance(strategy=InheritanceType.JOINED)
@JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.PROPERTY, property = "supporterType")
@JsonSubTypes({
@JsonSubTypes.Type(value = PersonSupporterEntity.class, name = "PERSON"),
@JsonSubTypes.Type(value = CompanySupporterEntity.class, name = "COMPANY")
})
@DiscriminatorColumn(name="supporter_type")
@Table(name = "supporter")
public class SupporterEntity extends UpdatableEntity {
private long id;
private SupporterType supporterType;
private PartnerEntity partner;
...
}
PersonSupporter
PersonSupporter
@Entity
@DiscriminatorValue("PERSON")
@Table(name = "person_supporter")
public class PersonSupporterEntity extends SupporterEntity {
...
}
CompanySupporter
CompanySupporter
@Entity
@DiscriminatorValue("COMPANY")
@Table(name = "company_supporter")
public class CompanySupporterEntity extends SupporterEntity {
...
}
我有另一个引用SupporterEntity的实体
I have another entity which references SupporterEntity
@Entity
@Table(name = "contact")
public class ContactEntity extends UpdatableEntity {
private long id;
private SupporterEntity supporter;
...
@ManyToOne // same error with @OneToOne
@JoinColumn(name = "supporter_id", referencedColumnName = "id", nullable = false)
public SupporterEntity getSupporter() {
return supporter;
}
...
}
存储库
@Transactional
@RepositoryRestResource(collectionResourceRel = "supporters", path = "supporters")
public interface SupporterEntityRepository extends JpaRepository<SupporterEntity, Long> {
@Transactional(readOnly = true)
@RestResource(path = "by-partner", rel = "by-partner")
public Page<SupporterEntity> findByPartnerName(@Param("name") String name, Pageable pageable);
}
@Transactional
@RepositoryRestResource(collectionResourceRel = "person_supporters", path = "person_supporters")
public interface PersonSupporterEntityRepository extends JpaRepository<PersonSupporterEntity, Long> {
}
@Transactional
@RepositoryRestResource(collectionResourceRel = "company_supporters", path = "company_supporters")
public interface CompanySupporterEntityRepository extends JpaRepository<CompanySupporterEntity, Long> {
}
@Transactional
@RepositoryRestResource(collectionResourceRel = "contacts", path = "contacts")
public interface ContactEntityRepository extends JpaRepository<ContactEntity, Long> {
@Transactional(readOnly = true)
@RestResource(path = "by-supporter", rel = "by-supporter")
public ContactEntity findBySupporterId(@Param("id") Long id);
}
我使用Spring Boot,Spring Data REST,Spring Data JPA,Hibernate,Jackson 。当我尝试使用这样的帖子请求创建一个新的ContactEntity时:
I use Spring Boot, Spring Data REST, Spring Data JPA, Hibernate, Jackson. When I try to create a new ContactEntity with a post request like this:
{
"supporter":"/supporters/52",
"postcode":"1111",
"city":"Test City 1",
"address":"Test Address 1",
"email":"test1@email.com",
"newsletter":true
}
我得到了这个例外:
Caused by: com.fasterxml.jackson.databind.JsonMappingException: Unexpected token (VALUE_STRING), expected FIELD_NAME: missing property 'supporterType' that is to contain type id (for class com.facer.domain.supporter.SupporterEntity)
at [Source: HttpInputOverHTTP@4321c221; line: 1, column: 2] (through reference chain: com.facer.domain.supporter.ContactEntity["supporter"])
at com.fasterxml.jackson.databind.JsonMappingException.from(JsonMappingException.java:148) ~[jackson-databind-2.4.4.jar:2.4.4]
2天后调试我发现了一种方法,但我猜对了。所以,如果我这样发布:
After 2 days of debugging I found a way, but I kinda guessed it. So if I post it like this:
{
"supporter":{
"supporterType":"PERSON",
"id":"52"
},
"postcode":"1111",
"city":"Test City 1",
"address":"Test Address 1",
"email":"test1@email.com",
"newsletter":true
}
它有效,但我不知道为什么。其他请求有什么问题?当引用的实体没有继承时,它就像其他地方一样。
It works, but I don't know why. What's wrong with the other request? It works like that everywhere else when the referenced entity does not have inheritance.
使用 RelProvider
:
- 不要使用
@JsonTypeInfo
-
为
SupporterEntity
子类创建RelProvider
@Component
@Order(Ordered.HIGHEST_PRECEDENCE)
public class SupporterEntityRelProvider implements RelProvider {
@Override
public String getCollectionResourceRelFor(final Class<?> type) {
return "supporters";
}
@Override
public String getItemResourceRelFor(final Class<?> type) {
return "supporter";
}
@Override
public boolean supports(final Class<?> delimiter) {
return org.apache.commons.lang3.ClassUtils.isAssignable(delimiter, SupporterEntity.class);
}
}
另见:
- https://jira.spring.io/browse/DATAREST-344
- http://docs.spring.io/spring-hateoas/docs/current/reference/html/#configuration.at-启用
- https://jira.spring.io/browse/DATAREST-344
- http://docs.spring.io/spring-hateoas/docs/current/reference/html/#configuration.at-enable