Question

I’m trying to translate a simple HQL to Criteria API, can anyone help me?
This is my HQL:

SELECT ch FROM Parent p JOIN p.childeren ch WHERE p.id = :id

As a result I get children. Important thing is there there is no relation from Child to Parent.
There is only relation in Parent to children like this:

@OneToMany(fetch = FetchType.LAZY, cascade = { CascadeType.ALL })
@JoinColumn(name="parent_id")
private List children;

How can I get the same results using criteria-api?

Answer 1

Only fetching an associated entity is a huge pain using the Criteria API. You would need sub-queries:

    DetachedCriteria subCriteria = DetachedCriteria.forClass(Parent.class);
    subCriteria.createCriteria("children", "c");
    subCriteria.setProjection(Projections.property("c.id"));
    subCriteria.add(Restrictions.eq("id", 1));
    // Assuming Children is the name of the class
    Criteria criteria = sess.createCriteria(Children.class);
    criteria.add(Subqueries.propertyIn("id", subCriteria));
    criteria.list();