When using Entity Graphs in JPA 2.1, is there a way of using the metamodel when there are Subgraphs of Subgraphs?

Question

For example, consider a Customer entity has a Set of Orders. Each Order has a Set of OrderItems.

I can do this with named attributes:

EntityGraph<Customer> eg = em.createEntityGraph(Customer.class);
Subgraph<Order> egChild = eg.addSubgraph("orders");
egChild.addAttributeNodes("orderItems");

If I was only interested in Orders, I can do this using the metamodel:

EntityGraph<Customer> eg = em.createEntityGraph(Customer.class);
eg.addSubgraph(Customer_.orders);

But, If I want the entire graph using only the metamodel, I can not do this:

EntityGraph<Customer> eg = em.createEntityGraph(Customer.class);
Subgraph<Set<Order>> egChild = eg.addSubgraph(Customer_.orders);
egChild.addAttributeNodes(Order_.orderItems);

The problem seems to be that

eg.addSubgraph(Customer_.orders)

returns a

Subgraph<Set<Order>> 

and not a

Subgraph<Order>

Is this a shortcoming of metamodel/entitygraphs, or am I missing something?

Answer 1

You could use the overloaded method:

Subgraph<Order> egChild = eg.addSubgraph(Customer_.orders.getName(), Order.class);