<persistence xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd" version="2.0">
	<persistence-unit name="manager1" transaction-type="RESOURCE_LOCAL">
		<provider>org.hibernate.ejb.HibernatePersistence</provider>
		<properties>
			<!-- jdbc connection -->
			<property name="hibernate.dialect" value="org.hibernate.dialect.HSQLDialect"/>
			<property name="hibernate.hbm2ddl.auto" value="update"/>
			<property name="hibernate.connection.driver_class" value="org.hsqldb.jdbcDriver"/>  
			<property name="javax.persistence.jdbc.user" value="sa"/>  
			<property name="javax.persistence.jdbc.password" value=""/>
			<property name="hibernate.connection.url" value="jdbc:hsqldb:mem:test"/>
			<property name="hibernate.hbm2ddl.auto" value="create-drop"/>
		</properties>
	</persistence-unit>
</persistence>

@Entity
public class EntityBean
{
	@Id
	@GeneratedValue(strategy = GenerationType.SEQUENCE)
	private Long id;
	
	@ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.PERSIST)
	private EntityBean child;
	
	public Long getId()
	{
		return id;
	}
	
	public EntityBean getChild()
	{
		return child;
	}
	
	public void setChild(EntityBean child)
	{
		this.child = child;
	}
}

public class EntityBeanTest
{
	private PersistenceUnitUtil persistenceUnitUtil;
	private EntityManagerFactory entityManagerFactory;
	private EntityManager entityManager;
	private EntityTransaction entityTransaction;
	private EntityBean parent;
	
	@Test
	public void checkEntityIdFromProxy()
	{
		EntityBean child = parent.getChild();
		
		assertFalse(persistenceUnitUtil.isLoaded(child));
		
		assertEquals(child.getId(), persistenceUnitUtil.getIdentifier(child));
	}

	@Before
	public void setUp()
	{
		entityManagerFactory = Persistence.createEntityManagerFactory("manager1");
		persistenceUnitUtil = entityManagerFactory.getPersistenceUnitUtil();
		entityManager = entityManagerFactory.createEntityManager();
		entityTransaction = entityManager.getTransaction();
		entityTransaction.begin();
		
		// create an entity bean
		EntityBean entityBean = new EntityBean();
		entityBean.setChild(new EntityBean());
		entityManager.persist(entityBean);
		
		entityManager.flush();
		
		// get the id of the parent entity
		Long id = entityBean.getId();
		
		// clear the first level cache
		entityManager.clear();

		// bring the parent back
		parent = entityManager.find(EntityBean.class, id);
	}
	
	@After
	public void tearDown()
	{
		entityTransaction.commit();
		entityManager.close();
		entityManagerFactory.close();
	}	
}