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PODoes @Loader work correctly on annotations (using JPA)?
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This is a somewhat contrived example meant to show a point. Here are two entity classes linked by a relationship and a named query: <pre><code>@Entity @NamedNativeQuery(name = "loadFoo", query = "select * from foos where bar_id = ?", resultClass = Foo.class) public class Bar { @Id private int id; @ManyToOne @Loader(namedQuery = "loadFoo") private Foo foo; public void setId(int id) { this.id = id; } public int getId() { return id; } public void setFoo(Foo foo) { this.foo = foo; } public Foo getFoo() { return foo; } } </code></pre> And then: <pre><code>@Entity @Table(name="foos") public class Foo { @Id @GeneratedValue private int id; @Column(name="bar_id") private int barId; public void setBarId(int barId) { this.barId = barId; } public int getBarId() { return barId; } public void setId(int id) { this.id = id; } public int getId() { return id; } } </code></pre> The odd thing is that the named query works just fine in unit testing: Here's the setup: <pre><code> Bar bar = new Bar(); entityManager.persist(bar); entityManager.flush(); Foo foo = new Foo(); foo.setBarId(bar.getId()); entityManager.persist(foo); entityManager.flush(); entityManager.clear(); </code></pre> And this correctly returns Foo, so there does not appear to be a problem with the named query: <pre><code> Foo foo2 = (Foo) entityManager.createNamedQuery("loadFoo").setParameter(1, bar.getId()).getSingleResult(); </code></pre> But the load does not: <pre><code> Bar bar2 = entityManager.find(Bar.class, bar.getId()); Foo foo3 = bar2.getFoo(); assertEquals(foo2.getId(), foo3.getId()); </code></pre> There are no errors thrown. The returned object is simply null. The @Loader annotation is in fact being processed by the persistence unit, because if I make the named query invalid, an exception will be thrown when getFoo() is called. But it never returns a correct value.
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Does @Loader work correctly on annotations (using JPA)?
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