Question

我有自引用类

@Entity
@Table(name = "contacts")
@Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
@Document(indexName = "contacts")
public class Contacts implements Serializable
{

private static final long serialVersionUID = 1L;

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

@Column(name = "username")
private String username;

@Column(name = "password_smartlpc")
private String password;

@Column(name = "full_name")
private String fullName;

@ManyToOne
private Contacts companyContact;
}

但对于我的一个数据库记录

id  full_name   username    password    company_contact_id  
5   JAK movies  abc          xyz               5

此记录将company_contact_id作为其自身ID。当检索进入自引用周期时。

Enter: com.fps.web.rest.errors.ExceptionTranslator.processRuntimeException() 
with argument[s] = 
[org.springframework.http.converter.HttpMessageNotWritableException: Could not 
 write content: Direct self-reference leading to cycle (through reference 
 chain: java.util.UnmodifiableRandomAccessList[2]-
 >com.fps.domain.Contacts["companyContact"]-
 >com.fps.domain.Contacts["companyContact"]); nested exception is 
 com.fasterxml.jackson.databind.JsonMappingException: Direct self-reference 
 leading to cycle (through reference chain: 
 java.util.UnmodifiableRandomAccessList[2]-
  >com.fps.domain.Contacts["companyContact"]-
 >com.fps.domain.Contacts["companyContact"])]

我已经尝试过工作

(fetch = FetchType.LAZY) = gives same error as above.
@JsonIgnore :  removes error but does not retrieves Company_Contact_id
@JsonManagedReference @JsonBackReference same as above.

不幸的是我无法更改数据库或更改它。因为它的遗产。我可以尝试更多的东西？感谢

Answer 1

在JHipster中尝试using DTOs，您将获得对JSON序列化的更多控制，而不是简单地暴露您的实体，尤其是当您受旧数据库架构约束时。

自我参考记录导致＆＃34;直接自我参考导致循环＆＃34;例外

1 个答案: