👀 Views: 88 💬 Answers: 1 📅 Created: 2025-07-27

java spring jpa postgresql lazy-loading Java

I'm dealing with Does anyone know how to Can someone help me understand This might be a silly question, but I'm encountering a `LazyInitializationException` while using Spring Data JPA in a multi-threaded environment..... My application is designed to fetch data from a PostgreSQL database, but I'm running into problems when trying to access properties of a lazily loaded entity outside of the transaction scope. I have the following entity setup: ```java @Entity public class User { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) private Long id; private String name; @OneToMany(mappedBy = "user", fetch = FetchType.LAZY) private List<Order> orders; } @Entity public class Order { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) private Long id; @ManyToOne @JoinColumn(name = "user_id") private User user; private Double amount; } ``` In my service, I'm trying to fetch a `User` and its associated `Order`s like so: ```java @Service public class UserService { @Autowired private UserRepository userRepository; @Transactional(readOnly = true) public User getUserWithOrders(Long userId) { return userRepository.findById(userId).orElseThrow(() -> new EntityNotFoundException("User not found")); } } ``` I then call this service method from a controller method: ```java @RestController @RequestMapping("/api/users") public class UserController { @Autowired private UserService userService; @GetMapping("/{id}") public ResponseEntity<User> getUser(@PathVariable Long id) { User user = userService.getUserWithOrders(id); // Simulate multi-threading issue by accessing orders in a different thread CompletableFuture.supplyAsync(() -> user.getOrders()).join(); return ResponseEntity.ok(user); } } ``` When I execute this code, I get a `LazyInitializationException` indicating that the `orders` collection could not be initialized because the session is closed. I've tried adding annotations like `@Transactional` at the controller level, but it seems to create a new session instead of reusing the one from the service method. Are there any recommended practices for handling lazy loading in a multi-threaded context, or should I consider switching to eager loading for specific use cases? Any insights on how to fix this issue would be greatly appreciated. Has anyone else encountered this? This issue appeared after updating to Java 3.11. Is this even possible? Thanks for your help in advance!