Strange Behavior with Java 17 and Hibernate Lazy Loading on Detached Entities
I'm working on a personal project and I'm working with a perplexing scenario with Hibernate's lazy loading in a Java 17 application. When I detach an entity from the session and later attempt to access its lazily loaded properties, I receive a `LazyInitializationException`, even though I've set up my entity relationships correctly. My entity looks like this: ```java @Entity public class User { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) private Long id; @OneToMany(mappedBy = "user", fetch = FetchType.LAZY) private List<Post> posts; // getters and setters } @Entity public class Post { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) private Long id; @ManyToOne @JoinColumn(name = "user_id") private User user; // getters and setters } ``` In my service, I'm fetching the user and then subsequently detaching it from the session. Here's the relevant portion of my code: ```java @Transactional public User getUserWithPosts(Long userId) { User user = userRepository.findById(userId).orElseThrow(() -> new EntityNotFoundException("User not found")); entityManager.detach(user); return user; } ``` After detaching the user and trying to access `user.getPosts()`, I see the following behavior: ``` org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: com.example.User.posts, no session or session was closed ``` I’ve tried using `Hibernate.initialize(user.getPosts())` before detaching the user, but it doesn’t seem to help. I also looked into using DTOs to fetch the required data in one go, but I prefer to maintain the separation of concerns in my application. What could be causing this scenario, and how can I access the lazy-loaded properties post-detachment without running into this exception? Any insights or best practices on handling this with Hibernate and Java 17 would be greatly appreciated. This is my first time working with Java LTS.