With spring boot - can't get all the fields when querying on multiples tables - spring-boot

Question

I'm trying to get information from both tables model and user_model but without success.
Tables have relations like these :
So i use HQL request to get this informations, here is the request :
#Repository
public interface UserRepository extends JpaRepository<User, Long> {
User findByUsername(String username);
#Query("SELECT m, um.hasWriteAccess FROM Model as m, UserModel as um "
+ "INNER JOIN m.userModel "
+ "INNER JOIN um.user as u "
+ "WHERE u.username=:username")
List<Model> findModelsForUser(#Param("username") String username);
}
But i get duplicate information without the hasWriteAccess field? Hum, what did i forget ? I don't understand why it doesn't work while the same SQL query gives me the expected result...
Here is the result i get :
{
"models": [
{
"displayName": "model1",
"type": "type1",
"description": "description model1",
...
=> Missing : "hasWriteAccess" : "1"
},
{
"displayName": "model1",
"type": "type1",
"description": "description model1",
...
=> Missing : "hasWriteAccess" : "1"
},
{
"displayName": "model4",
"type": "type2",
"description": "description model4",
...
=> Missing : "hasWriteAccess" : "1"
},
{
"displayName": "model4",
"type": "type2",
"description": "description model4",
...
=> Missing : "hasWriteAccess" : "1"
},
...
],
"CENTRAL_GIT_URL": "xxxx",
"CENTRAL_GIT_USER": "xxxx",
"CENTRAL_GIT_PASS": "xxxx"
}
This is the controller with which I call the service that initiates the request :
#PostMapping("/authentication")
public ResponseEntity<HashMap> process(#RequestBody Map<String, String> request) throws Exception {
List<Model> models = new ArrayList<Model>();
models = genericService.findModelsForUser( request.get("username"));
HashMap<String, Object> map = new HashMap<>();
map.put("CENTRAL_GIT_USER", env.getProperty("spring.constant.git.central.user"));
map.put("CENTRAL_GIT_PASS", env.getProperty("spring.constant.git.central.password"));
map.put("CENTRAL_GIT_URL", env.getProperty("spring.constant.git.central.url"));
map.put("models",models);
return new ResponseEntity<HashMap>(map, HttpStatus.OK);
}
It may be useful to show my entities. So I have entity User :
#Entity
#Table(name = "user")
#JsonIgnoreProperties(value = { "password" })
public class User implements Serializable {
private static final long serialVersionUID = 7182498683194688448L;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "user_id")
private Long id;
...
#ElementCollection
#CollectionTable(name = "user_role", joinColumns = #JoinColumn(name = "user_id"))
#Column(name = "role_name")
private List<String> roles = new ArrayList<>();
#OneToMany(mappedBy="user",cascade = CascadeType.ALL)
#JsonBackReference
private List<UserModel> userModel;
... getters ans setters
And entity Model :
#Entity
#Table(name="model")
public class Model implements Serializable {
private static final long serialVersionUID = 1125066441066336997L;
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
#Column(name="model_id")
private Long id;
...
#OneToMany(mappedBy="model",cascade = CascadeType.ALL)
#JsonBackReference
private List<UserModel> userModel;
... getters and setters
And entity UserModel :
#Entity
#Table(name="user_model")
public class UserModel implements Serializable{
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
#Column(name = "user_model_id")
private long id;
#ManyToOne
#JoinColumn(name="user_id")
#JsonManagedReference
private User user;
#ManyToOne
#JoinColumn(name="model_id")
#JsonManagedReference
private Model model;
#Column(name="is_activated")
private boolean isActivated;
#Column(name="has_write_access")
private boolean hasWriteAccess;
... getters and setters
Can you tell me where is my mistake ? Thanks

Answer 1

To workaround this issue try to use 'distinct' in the query:
#Query("select distinct m from Model m join m.userModel um join um.user u where u.username = ?1")
List<Model> findModelsByUserName(String userName);
I think there is a bug in Spring Data JPA that leads to this situation.
See my 'investigation' about this problem.
Also to workaround the issue try to use Hibernate 5.2.12 instead of 5.0.12 (by default)...

Answer 2

With your help i modified my request like this :
#Query("select distinct um from UserModel as um inner join um.user as u where u.username =:username")
List<Object[]> findModelsForUser(#Param("username") String username);
And i get the result that i expected. Thanks