EclipseLink JPA CriteriaBuilder generated invalid SQL Syntax - jpa-2.0

Question

I have two objects, both defined as entities, one containing the other as follows:
#Entity
public class TestC
{
#Id #GeneratedValue
private Integer id;
#ManyToOne (cascade = {CascadeType.PERSIST, CascadeType.MERGE} )
TestD d;
}
#Entity
public class TestD
{
#Id #GeneratedValue
private Integer id;
String moo;
}
The entities are persisted:
TestC c2 = new TestC();
TestD d2 = new TestD();
d2.moo = "d2";
c2.d = d2;
em.getTransaction().begin();
em.persist(d2);
em.persist(c2);
em.getTransaction().commit();
I am trying to query for TestC objects with an instance of TestD:
CriteriaBuilder builder = em.getCriteriaBuilder();
CriteriaQuery<TestC> query = builder.createQuery(TestC.class);
Root<TestC> from = query.from(TestC.class);
ParameterExpression<TestD> pe = builder.parameter(TestD.class);
query.where(builder.equal(pe, from.<TestD>get("d")));
TestC found = em.createQuery(query)
.setParameter(pe, d2)
.getSingleResult();
But EclipseLink kicks out the following error when running the query (note the SQL is invalid near "(? = )", there is no column name for the TestD object):
Exception in thread "main" Local Exception Stack:
Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.3.2.v20111125-r10461): org.eclipse.persistence.exceptions.DatabaseException
Internal Exception: java.sql.SQLException: Invalid argument value: java.io.NotSerializableException
Error Code: 0
Call: SELECT t1.ID, t1.D_ID FROM TESTD t0, TESTC t1 WHERE ((? = ) AND (t0.ID = t1.D_ID))
bind => [1 parameter bound]
Query: ReadAllQuery(referenceClass=TestC sql="SELECT t1.ID, t1.D_ID FROM TESTD t0, TESTC t1 WHERE ((? = ) AND (t0.ID = t1.D_ID))")
Am I building the query wrong?
Thanks for any help!

Answer 1

It is not documented in the JavaDoc, but ParameterExpression should be second argument. Order follows same logic as equal(Expression x, java.lang.Object y). Additionally you need .select. EclipseLink (at least 2.3.0) works also without, but according specification leaving select/multiselect out is not portable:
Portable applications should use the select or multiselect method to
specify the query’s selection list. Applications that do not use one
of these methods will not be portable.
After those changes, correct approach is:
CriteriaQuery<TestC> query = builder.createQuery(TestC.class);
Root<TestC> from = query.from(TestC.class);
ParameterExpression<TestD> pe = builder.parameter(TestD.class);
query.select(from)
.where(builder.equal(from.<TestD>get("d"), pe));
TestC found = em.createQuery(query)
.setParameter(pe, d)
.getSingleResult();