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copied!<p>I believe property access vs. field access is subtly different with regards to lazy initialisation.</p> <p>Consider the following mappings for 2 basic beans:</p> <pre class="lang-xml prettyprint-override"><code><hibernate-mapping package="org.nkl.model" default-access="field"> <class name="FieldBean" table="FIELD_BEAN"> <id name="id"> <generator class="sequence" /> </id> <property name="message" /> </class> </hibernate-mapping> <hibernate-mapping package="org.nkl.model" default-access="property"> <class name="PropBean" table="PROP_BEAN"> <id name="id"> <generator class="sequence" /> </id> <property name="message" /> </class> </hibernate-mapping> </code></pre> <p>And the following unit tests:</p> <pre><code>@Test public void testFieldBean() { Session session = sessionFactory.openSession(); Transaction tx = session.beginTransaction(); FieldBean fb = new FieldBean("field"); Long id = (Long) session.save(fb); tx.commit(); session.close(); session = sessionFactory.openSession(); tx = session.beginTransaction(); fb = (FieldBean) session.load(FieldBean.class, id); System.out.println(fb.getId()); tx.commit(); session.close(); } @Test public void testPropBean() { Session session = sessionFactory.openSession(); Transaction tx = session.beginTransaction(); PropBean pb = new PropBean("prop"); Long id = (Long) session.save(pb); tx.commit(); session.close(); session = sessionFactory.openSession(); tx = session.beginTransaction(); pb = (PropBean) session.load(PropBean.class, id); System.out.println(pb.getId()); tx.commit(); session.close(); } </code></pre> <p>You will see the subtle difference in the selects required:</p> <pre class="lang-none prettyprint-override"><code>Hibernate: call next value for hibernate_sequence Hibernate: insert into FIELD_BEAN (message, id) values (?, ?) Hibernate: select fieldbean0_.id as id1_0_, fieldbean0_.message as message1_0_ from FIELD_BEAN fieldbean0_ where fieldbean0_.id=? 0 Hibernate: call next value for hibernate_sequence Hibernate: insert into PROP_BEAN (message, id) values (?, ?) 1 </code></pre> <p>That is, calling <code>fb.getId()</code> requires a select, whereas <code>pb.getId()</code> does not.</p>

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