Get org.hibernate.LazyInitializationException in spring boot integration test

Question

I'm trying to write integration test for Spring Boot application. I have Product and GalleryImage domain model. They are in one-to-many relationship.

public class Product {
    ...

    @OneToMany(mappedBy = "product")
    private List<GalleryImage> galleryImages;
}

I have a integration test as below:

@Test
public void testProductAndGalleryImageRelationShip() throws Exception {
    Product product = productRepository.findOne(1L);
    List<GalleryImage> galleryImages = product.getGalleryImages();
    assertEquals(1, galleryImages.size());
}

However, this test gives me a LazyInitializationException. I searched on Google and StackOverFlow, it says that the session is closed after productRepository.findOne(1L), since galleryImages are lazily loaded, so galleryImages.size() gives me this exception.

I have tried to add a @Transactional annotation on the test, but it's still not working.

Answer 1

Hibernate Session has been closed after following line productRepository.findOne(1L).

You can try to do Hibernate.initialize(product.getGalleryImages())

public static void initialize(Object proxy)
                   throws HibernateException

Force initialization of a proxy or persistent collection. Note: This only ensures intialization of a proxy object or collection; it is not guaranteed that the elements INSIDE the collection will be initialized/materialized.

To avoid Hibernate.initialize you can create a service.

@Service
@Transactional
public class ProductService {

    @Transactional(readOnly = true)
    public List<GalleryImage> getImages(final long producId) throws Exception {
      Product product = productRepository.findOne(producId);
      return product.getGalleryImages();
  }
}

If you do use Spring Data JPA in you application then dynamic finder is a good alternative.