Question

I am creating a simple Java EE web application.

Among other entities, I have the User entity, which owns some Unit objects. The entitie classes are build correctly and the user has a one to many relationship with the unit objects. I want to retrieve a list with all the Units of the logged in user.

Therefore in the unit EJB I must have the following method

public List<Unit> findUnitsByOwner(User user)

I am very unfamiliar with the persistence api and I am not being able to create a query which would retrieve the units that belong to a certain user.

Can someone help with the method body please?

Answer 1

Well the query is very easy :

select unit from User user inner join user.units unit

But you could also do the easier

return user.getUnits();