JsonIgnore and JsonBackReference are being Ignored - json

Question

i'm using spring 4.0.1 , hibernate 4.3.5 ,jackson 1.9.2 and STS IDE
I'm creating a RESTful webservice that returns a data in JSON format
when i use Hibernate code generator it generates getters and setter of associated entities annotated by #OneToMany(fetch = FetchType.LAZY, mappedBy = "user") for the source
and #ManyToOne(fetch = FetchType.LAZY) for the reference
which causes an infinite recursion during serialization. I tried using Jackson's #JsonIgnore and #JsonBackReference annotations to fix the problem but it seems as if they are being totally ignored and the infinite recursion is still occurring.
Caused by: com.fasterxml.jackson.databind.JsonMappingException: Infinite recursion (StackOverflowError)
This is my entity classes
User.class
//i get that suggestion from some sites
#JsonIgnoreProperties({ "hibernateLazyInitializer", "handler" })
#Entity
#Table(name = "user", catalog = "someSchema")
public class User implements java.io.Serializable {
private String name;
private String password;
private String username;
private Set<Telephone> telephones = new HashSet<Telephone>(0);
#JsonManagedReference
#OneToMany(fetch = FetchType.LAZY, mappedBy = "user")
public Set<Telephone> getTelephones() {
return this.telephones;
}
public void setTelephones(Set<Telephone> telephones) {
this.telephones = telephones;
}
}
Telephone.class
#Entity
#Table(name = "telephone", catalog = "someSchema")
public class Telephone implements java.io.Serializable {
private User user;
private String telephone;
#ManyToOne(fetch = FetchType.LAZY)
//tried #JsonIgnore only and both
#JsonIgnore
//tried #JsonBackReference only and both
#JsonBackReference
#JoinColumn(name = "user_id", nullable = false)
public User getUser() {
return this.user;
}
#JsonIgnore
#JsonBackReference
public void setUser(User user) {
this.user = user;
}
}
concerning registering jackson to my application, i used xml config
<mvc:annotation-driven>
<mvc:message-converters>
<bean
class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
<property name="objectMapper">
<bean
class="web.jsonConverters.HibernateAwareObjectMapper" />
</property>
</bean>
</mvc:message-converters>
</mvc:annotation-driven>
and mapper class
public class HibernateAwareObjectMapper extends ObjectMapper {
public HibernateAwareObjectMapper() {
Hibernate4Module hm = new Hibernate4Module();
registerModule(hm);
}
}
Do you have any idea why the Jackson annotations are being ignored?
any help will be appreciated...

Answer 1

use
import com.fasterxml.jackson.annotation.JsonBackReference;
instead of
import org.codehaus.jackson.annotate.JsonBackReference;

Answer 2

i found a way by annotating the setter by #Transient
idont know why but it works fine
User.class
//i get that suggestion from some sites
#JsonIgnoreProperties({ "hibernateLazyInitializer", "handler" })
#Entity
#Table(name = "user", catalog = "someSchema")
public class User implements java.io.Serializable {
private String name;
private String password;
private String username;
private Set<Telephone> telephones = new HashSet<Telephone>(0);
#OneToMany(fetch = FetchType.LAZY, mappedBy = "user")
public Set<Telephone> getTelephones() {
return this.telephones;
}
public void setTelephones(Set<Telephone> telephones) {
this.telephones = telephones;
}
}
Telephone.class
#Entity
#Table(name = "telephone", catalog = "someSchema")
public class Telephone implements java.io.Serializable {
private User user;
private String telephone;
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "user_id", nullable = false)
public User getUser() {
return this.user;
}
#Transient
public void setUser(User user) {
this.user = user;
}
}
Another Naive Solution
I solved it manually in my RESTful Controller
by loop over the set of telephones and set user to null
#RestController
#RequestMapping("/user")
public class UserController extends ParentController {
static final Logger logger = Logger.getLogger(UserController.class.getName());
#Autowired
IUserDao iuserdao;
#RequestMapping(value = "/signin", method = RequestMethod.POST)
public ResponseEntity<User> signin(#RequestBody LoginWrapper login) {
System.out.println("==============GET USER==============");
try {
User user = iuserdao.signin(login);
if (user == null) {
HttpHeaders httpHeaders = new HttpHeaders();
httpHeaders.set(ERR_HEADER_NAME, "user not exist");
return new ResponseEntity<User>(httpHeaders, HttpStatus.NOT_FOUND);
} else {
List<Telephone> tels=user.getTelephones();
for (Telephone telephone : tels) {
telephone.setUser(null);
}
return new ResponseEntity<User>(user, HttpStatus.OK);
}
} catch (Exception e) {
System.out.println(e.getMessage());
return null;
}
}
still need a better answer concerning Jackson problem..