I’m working on a Spring Boot application using JPA and Hibernate for ORM. I have a problem with lazy loading and transactions that I can’t seem to resolve.

Here is my setup:

Spring Boot 2.5.2
Hibernate 5.4.32
MySQL 8.0.25

@Entity
public class Author {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    
    private String name;

    @OneToMany(mappedBy = "author", fetch = FetchType.LAZY)
    private List<Book> books;

    // Getters and setters
}

@Entity
public class Book {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    
    private String title;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "author_id")
    private Author author;

    // Getters and setters
}

@Service
public class AuthorService {
    
    @Autowired
    private AuthorRepository authorRepository;

    @Transactional
    public Author getAuthorWithBooks(Long authorId) {
        Author author = authorRepository.findById(authorId).orElseThrow(() -> new EntityNotFoundException("Author not found"));
        // Trying to access lazy-loaded books
        author.getBooks().size();
        return author;
    }
}

public interface AuthorRepository extends JpaRepository<Author, Long> {
}

When I call the getAuthorWithBooks method, it throws a LazyInitializationException if the author.getBooks().size() line is executed outside of the transactional method. However, I was under the impression that the @Transactional annotation would handle this.

How can I ensure that the books collection is properly loaded within the transactional context? Is there a better way to handle this kind of lazy loading in JPA?