I have a problem with lazy initialization in my Spring Boot application. I have an entity with lazy field Role, and I they have LazyInitializationException in My Spring Security (UserDetailsService) method, but in controller it's ok.
Can you explaine to me how Spring Boot works with fetch = FetchType.LAZY ? Why it does not work Spring Security UserDetailsService and work in controller methods?
I did not find any guide about this. Thanks!
Spring Boot :
@SpringBootApplication
public class App {
public static void main(String[] args) throws Exception {
SpringApplication.run(App.class, args);
}
}
An Entity:
@Entity
@Table(name = "users")
@Getter
@Setter
@NoArgsConstructor
public class Users {
@ManyToMany(fetch = FetchType.LAZY)
@JoinTable(name = "Users_Role", joinColumns = @JoinColumn(name = "User_id", referencedColumnName = "id"),
inverseJoinColumns = @JoinColumn(name = "role_id", referencedColumnName = "id"))
private Set<Role> roles = new HashSet<Role>();
}
My Service:
@Transactional(readOnly = true)//does not matter
public Users getUserByLogin(String login) {
return usersRepository.findOneByLogin(login);
}
@Transactional(readOnly = true)
public Users getUserByLoginWithRoles(String login) {
Users oneByLogin = usersRepository.findOneByLogin(login);
logger.debug("User was initialize with Roles: " + oneByLogin.getRoles().size()); // force initialize of roles and it works!
return oneByLogin;
}
@Transactional(readOnly = true)//does not matter
public Users testGetUser() {
Users oneByLogin = usersRepository.getOne(1L);
return oneByLogin;
}
@Transactional(readOnly = true)//does not matter
public Users testFindUser() {
Users oneByLogin = usersRepository.findOne(1L);
return oneByLogin;
}
And I have Spring Security UserDetailsService:
@Service
public class UserDetailsServiceImpl implements UserDetailsService {
@Autowired
private Services services;
@Override
public UserDetails loadUserByUsername(String login) throws UsernameNotFoundException {
Users user;
Users userFetchedViaGet = services.testGetUser();
Users userFetchedViaCustomMethod = services.getUserByLogin(login);
Users userFetchedViaFind = services.testFindUser();
Users userFetchedWithRoles = services.getUserByLoginWithRoles(login);
try {
userFetchedViaGet.getRoles().add(new Role("test"));
} catch (Exception e) {
e.printStackTrace();//LazyInitializationException: failed to lazily initialize a collection of role: , could not initialize proxy - no Session
}
try {
userFetchedViaCustomMethod.getRoles().add(new Role("test"));
} catch (Exception e) {
e.printStackTrace();//LazyInitializationException: failed to lazily initialize a collection of role: , could not initialize proxy - no Session
}
try {
userFetchedViaFind.getRoles().add(new Role("test")); //LazyInitializationException: failed to lazily initialize a collection of role: , could not initialize proxy - no Session
} catch (Exception e) {
e.printStackTrace();
}
//some code
}
}
And My Controller (All methods works! But there is have to excpetion happen, because there is no session and Lazy fetch type):
@RequestMapping(value = "/test", method = RequestMethod.GET)
public String test() {
Users userFetchedViaGet = services.testGetUser();
Users userFetchedViaCustomMethod = services.getUserByLogin("ADMIN");
Users userFetchedViaFind = services.testFindUser();
Users userFetchedWithRoles = services.getUserByLoginWithRoles("ADMIN");
try {
userFetchedViaGet.getRoles().add(new Role("test"));
} catch (Exception e) {
e.printStackTrace();
}
try {
userFetchedViaCustomMethod.getRoles().add(new Role("test"));
} catch (Exception e) {
e.printStackTrace();
}
try {
userFetchedViaFind.getRoles().add(new Role("test"));
} catch (Exception e) {
e.printStackTrace();
}
//some code
}
