Jakson IllegalArgumentException: Can not handle managed/back reference

Question

CONTEXT:

I have 2 webapps:

• front (spring mvc)
• webservice (spring rest)

both communicate by webservice. I'm trying to generate an objet (CounterDTO) in webservice webapp from json like this :

ObjectMapper mapper = new ObjectMapper(); mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false); CounterDTO counterDTO = mapper.readValue(json.get(objName).toString(), CounterDTO.class);

ERROR:

When I try to build an objet with a json, I have this error:

java.lang.IllegalArgumentException: Can not handle managed/back reference 'entreprise-agency': back reference type (java.util.Set) not compatible with managed type (com.mypackage.Agency)

JSON sent:

{"id":null,"code":"SKYUE586","name":"name 1"}

I have 3 entities like this :

@Entity
@Table(name = "AGENCY")
public class Agency {
    ...
    @ManyToOne(optional = false)
    @JoinColumn(name = "ID_Entreprise")
    @JsonManagedReference(value = "entreprise-agency")
    private Entreprise entreprise;

    @OneToMany(mappedBy = "agency", cascade = CascadeType.ALL, fetch = FetchType.EAGER)
    @JsonBackReference(value = "agency-counter")
    private Set<Counter> counters = new HashSet<Counter>();
   ...
}

.

Entity
@Table(name = "COUNTER")
public class Counter {
    ...
    @ManyToOne(optional = false)
    @JoinColumn(name = "ID_Agence")
    // @JsonBackReference
    @JsonManagedReference(value = "agency-counter")
    private Agency agency;
    ...
}

.

@Entity
@Table(name = "ENTREPRISE")
public class Entreprise {
    ...
    @OneToMany(mappedBy = "entreprise", cascade = CascadeType.ALL, fetch = FetchType.EAGER)
    @JsonBackReference(value = "entreprise-agency")
    private Set<Agency> agencies = new HashSet<Agency>();
   ...
}

and DTO

public class CounterDTO {
    private Integer id;
    private String code;
    private String name;
    ...
}

QUESTION:

How can I properly handle managed/back jackson reference ?

I've also tried to use this tag on my entities

@JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "id")

Thanks

Answer 1

I've resolved issue by using

Gson library

Instead of ObjectMapper