In my domain model, a membership belongs to a restaurant (eager), and a restaurant has many locations (lazy).

// Membership.kt
@ManyToOne
@JoinColumn(name = "restaurantId", referencedColumnName = "restaurantId", insertable = false, updatable = false)
lateinit var restaurant: Restaurant

// Restaurant.kt
@OneToMany
@JoinColumn(name = "restaurantId", referencedColumnName = "restaurantId", insertable = false, updatable = false)
var locations: MutableSet<Location> = mutableSetOf()

I have an entity graph in Membership.kt specifying that I want to load membership.restaurant.locations:

@NamedEntityGraph(
    name = "Membership.WithLocations",
    attributeNodes = [
        NamedAttributeNode("restaurant", subgraph = "Restaurant.WithLocations")
    ],
    subgraphs = [
        NamedSubgraph(
            name = "Restaurant.WithLocations",
            attributeNodes = [
                NamedAttributeNode("locations")
            ]
        )
    ]
)

In my service layer, I want a method that saves a membership and returns it with this entity graph applied. Here’s what I tried:

@Transactional
fun saveAndRefresh(membership: Membership, entityGraphName: String): Membership {
    membershipRepository.save(membership)

    val newMembership = entityManager.find(Membership::class.java, membership.id)
    entityManager.refresh(
        newMembership,
        mapOf("javax.persistence.fetchgraph" to entityManager.getEntityGraph(entityGraphName))
    )

    return newMembership
}

But I find that membership.restaurant.locations still has not been initialized. Why not?

I have tried using entityManager.flush() after the save, and also fully detaching the membership after saving with entityManager.detach(membership), but neither helps.