I am getting an exception when trying to "serialize" an object graph to xml using the jdk 1.4 XMLEncoder class. It seems when a collection is encountered within the graph, then something goes awry.
This only happens after the object has been made persistent. That is, if I encode the object graph before the call to session.save() then, everything works just fine. However, any call to encoder.writeObject() after calling session.save() does not work properly.
I have seen references to a similar problem in the
2.1.5 release notes and a corresponding fix. However, if anyone has experience or would just like to share woes, I'd greatly appreciate it.
I wrote a sample app to illustrate the problem and have included the pertinent snippets below the signagure line.
Thanks for your attention,
Dan
Hibernate version: 2.1.6
Mapping documents:
Code:
<!-- from FieldDefinition.hbm.xml -->
<subclass
name="com.bequeaith.meta.ChoiceFieldDefinition"
dynamic-update="false"
dynamic-insert="false"
discriminator-value="ChoiceFieldDefinition">
<set name="choices" lazy="false" inverse="false" cascade="all" sort="unsorted">
<cache usage="transactional"/>
<key column="FK_CHOICE_FIELD_DEFINITION">
</key>
<one-to-many class="com.bequeaith.meta.Choice"/>
</set>
</subclass>
<!--from choice.hbm.xml -->
<class
name="com.bequeaith.meta.Choice"
table="CHOICE"
dynamic-update="false"
dynamic-insert="false">
<id name="identifier" column="PK" type="java.lang.Long">
<generator class="native">
</generator>
</id>
<property name="value" type="java.lang.String" update="true" insert="true" access="property" column="VALUE"/>
</class>
Code between sessionFactory.openSession() and session.close():Code:
public void testFieldDefinition() throws Exception
{
Session session = null;
XMLEncoder encoder = null;
try
{
SessionFactory factory = new Configuration().configure().buildSessionFactory();
session = factory.openSession();
ChoiceFieldDefinition cars = new ChoiceFieldDefinition(CARS);
cars.addChoice("BMW");
cars.addChoice("Ferrari");
cars.addChoice("TVR");
cars.addChoice("Lamborghini");
session.saveOrUpdate(cars);
session.flush();
assertTrue("Session closed", session.isOpen());
encoder = new XMLEncoder(new BufferedOutputStream(new FileOutputStream("./testxmloutput.xml")));
encoder.writeObject(cars);
encoder.close();
}
finally
{
session.close();
}
Full stack trace of any exception that occurs:Code:
net.sf.hibernate.LazyInitializationException: Failed to lazily initialize a collection - no session or session was closed
at net.sf.hibernate.collection.PersistentCollection.initialize(PersistentCollection.java:242)
at net.sf.hibernate.collection.PersistentCollection.read(PersistentCollection.java:74)
at net.sf.hibernate.collection.Set.size(Set.java:106)
at java.util.AbstractSet.equals(AbstractSet.java:72)
at java.beans.DefaultPersistenceDelegate.equals(DefaultPersistenceDelegate.java:207)
at java.beans.DefaultPersistenceDelegate.doProperty(DefaultPersistenceDelegate.java:220)
at java.beans.DefaultPersistenceDelegate.initBean(DefaultPersistenceDelegate.java:254)
at java.beans.DefaultPersistenceDelegate.initialize(DefaultPersistenceDelegate.java:395)
at java.beans.PersistenceDelegate.writeObject(PersistenceDelegate.java:103)
at java.beans.Encoder.writeObject(Encoder.java:55)
at java.beans.XMLEncoder.writeObject(XMLEncoder.java:250)
at java.beans.Encoder.writeExpression(Encoder.java:260)
at java.beans.XMLEncoder.writeExpression(XMLEncoder.java:363)
at java.beans.PersistenceDelegate.writeObject(PersistenceDelegate.java:100)
at java.beans.Encoder.writeObject(Encoder.java:55)
at java.beans.XMLEncoder.writeObject(XMLEncoder.java:250)
at java.beans.Encoder.writeObject1(Encoder.java:192)
at java.beans.Encoder.cloneStatement(Encoder.java:205)
at java.beans.Encoder.writeStatement(Encoder.java:236)
at java.beans.XMLEncoder.writeStatement(XMLEncoder.java:326)
at java.beans.XMLEncoder.writeObject(XMLEncoder.java:253)
at com.bequeaith.meta.TestMeta.testFieldDefinition(TestMeta.java:82)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at junit.framework.TestCase.runTest(TestCase.java:154)
at junit.framework.TestCase.runBare(TestCase.java:127)
at junit.framework.TestResult$1.protect(TestResult.java:106)
at junit.framework.TestResult.runProtected(TestResult.java:124)
at junit.framework.TestResult.run(TestResult.java:109)
at junit.framework.TestCase.run(TestCase.java:118)
at junit.framework.TestSuite.runTest(TestSuite.java:208)
at junit.framework.TestSuite.run(TestSuite.java:203)
at junit.textui.TestRunner.doRun(TestRunner.java:116)
at com.intellij.rt.execution.junit2.IdeaJUnitAgent.doRun(IdeaJUnitAgent.java:57)
at junit.textui.TestRunner.start(TestRunner.java:172)
at com.intellij.rt.execution.junit.TextTestRunner2.startRunnerWithArgs(TextTestRunner2.java:23)
at com.intellij.rt.execution.junit2.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:97)
at com.intellij.rt.execution.junit2.JUnitStarter.main(JUnitStarter.java:31)
Login
FAQ
Search