👀 Views: 163 💬 Answers: 1 📅 Created: 2025-06-07

java spring-data-jpa hibernate Java

I've tried everything I can think of but I'm migrating some code and I've been struggling with this for a few days now and could really use some help. I'm running into a `LazyInitializationException` when trying to access a collection from an entity that is fetched lazily. I have a `User` entity that has a one-to-many relationship with `Order` entities, defined like this: ```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; private String product; @ManyToOne @JoinColumn(name = "user_id") private User user; } ``` In my repository, I have the following method to fetch a user by ID: ```java public interface UserRepository extends JpaRepository<User, Long> { Optional<User> findById(Long id); } ``` When I fetch a user like this: ```java User user = userRepository.findById(userId).orElseThrow(); List<Order> orders = user.getOrders(); // This line throws LazyInitializationException ``` I realize that this is happening because the session is closed by the time I'm trying to access `orders`. I've tried several things like enabling OpenSessionInView, but it doesn't seem to fit well with my architecture since I am building a REST API and want to avoid keeping the session open during request processing. I've also considered using `JOIN FETCH` in my query to eagerly fetch the orders, but I want to maintain the separation of concerns in my repository. Is there a recommended approach to handle this without resorting to `JOIN FETCH` or keeping the session open? Any insights on best practices around this scenario would be greatly appreciated! How would you solve this? Is there a simpler solution I'm overlooking?