JPA lazy loading with Firebirdsql

I'm trying to use FetchType.Lazy in @OneToOne associations, with a firebirdsql database.
Toplink JPA generates the sql query as follow:
SELECT FIELD1, FIELD2, _TOPLINK_FIELD3_VH, ... FROM TABLE.....
This select gets this error msg:
Exception [TOPLINK-4002] (Oracle TopLink Essentials - 2006.8 (Build 060829)): oracle.toplink.essentials.exceptions.DatabaseException
Internal Exception: org.firebirdsql.jdbc.FBSQLException: Exception. nullError Code: 0
(it can't find the TOPLINKFIELD3_VH field)
Is this an issue related to firebirdsql support on Toplink?
Or is it a issue related to firebirdsql JDBC driver/database?

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db

Similar Messages

Hibernate lazy loading with spring

Has anyone been able to successfully implement the org.springframework.orm.hibernate3.support.PortletOpenSessionInViewInterceptor to enable hibernate lazy loading with page flows? Any examples would be helpful.
Thanks

Don't double post. I've removed the thread you started 3 hrs 16 minutes after this one with the identically same question.
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JPA - lazy loading for LOB field

Hi all,
JPA 1.0 specification mandates that all JPA-compliant implementation support lazy loading for certain kind of entity field.
For LOB fields lazy loading is OPTIONAL.
I am experiencing odd runtime behaviors on my custom software which would point to this feature not being supported.
Can anyone please tell me if SAP JPA 1.0 implementation on NW CE 711 implements this feature or not?
Thanks in advance
Regards
Vincenzo

Hi Vincenco,
I am sure that this is the same as with single-valued relationships (@OneToOne, @ManyToOne): Lazy loading would require bytecode manipulation/generation, so SAP JPA does not support it in 7.20 (and of course not in 7.11)
See tulsi jiddimani's elaborate answer here: Re: JPA: Documentation on LazyLoad.
In 7.30 enhancements, you really can find lazy loading support for single-valued relationships with getReference.
http://help.sap.com/saphelp_nw73/helpdata/en/68/f676ef36094f4381467a308a98fd2a/content.htm
but @Lob and @Basic is not mentioned.
If you need lazy loading in 7.11, you have two alternatives:
1. Put the Lob fields into separate entities, work around the missing feature in SAP JPA with ugly @OneToMany - Relations
2. Use another persistence provider like EclipseLink, read Sabine Heider's blogs about integrattion of EclipseLink in SAP NetWeaver and static bytecode weaving for lazy loading. /people/sabine.heider/blog
Regards
Rolf

Toplink JPA LAZY loading in Java SE works without javaagent?

hi there,
I tought that mappings like
@JoinColumn(name = "join_col_name")
@ManyToOne(cascade=CascadeType.ALL, fetch=FetchType.LAZY)
private RelatedObject relObj;
with TopLink JPA in Java SE environment works ONLY with the
-javaagent:toplink-essentials-agent.jar
JVM parameter?
the strange thing is: I did 2 test runs, with and without the java agent parameter. I also could see that in the first case the weaver is working, in the second the property "toplink.weaving=false" is printed to the console BUT if I access the LAZY mapped attribute of the object instance it works in both cases - I expected a NullPointerEx. in the case without the javaagent.
Is there anything I missed?
Hans

Chris,
thank for for the tip about verifying lazy or eager fetching. The results are interesting - or better: confusing - to me:
I have built a test project with 3 entities:
Entity A hast @OneToMany to Entity B and
Entity B has ManyToONe to Entity C
A <-- B --> C
ALL relations are marked with FetchType.LAZY in all directions.
When I simply run the test project via main()-method out of eclipse, WITHTOUT specifycing a -javaagent parameter in the run dialog, I can confirm using your test case that the realtion IS LAZILY FETCHED.
So, I do not really know how this should work without the javaagent.
You mentioned statically weaved classed - is this the default case when no agent is present, how is it done? Toplink logging says that weaving is NOT active:
ServerSession(16821027)--Thread(Thread[main,5,main])--property=toplink.weaving; value=false
so how can the lazy loading work then?
regards,
Hans

It doesn�t work lazy loading with remote client (toplink)

I am trying to use lazy loading in a @ManyToOne field but I get an exception. I have been reading in some oracle tutorials that it's necesary use -javaagent:.../lib/toplink-essentials-agent.jar for that it works because this argument activate dynamic weaving in JavaSE. I have put this command line argument javaagent but it doesn't work. Why? Can I have to do another thing? I have done a lot of tests in base to comments read in another forums but I only obtains an exception.
Caused by: java.io.IOException: Mismatched serialization UIDs
NOTE: The server use toplink and the remote client query the entitties through a session bean of the server. Besides, I am using Glassfish (Sun application server and toplink).
Thanks in advance.
hayken

At first, thank you for your reply.
I know that I haven´t explained the problem too well. I have a stateless bean with one remote method that execute a query an returns an entity like this
@Entity
public class ModuloEntity extends Serializable
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long idModulo;
private String nombre;
@ManyToOne(fetch=FetchType.LAZY)
@JoinColumn(name="IdProyecto")
private ProyectoEntity proyecto;
The remote client invoke this method and in that moment I get this exception.
21-may-2007 18:55:48 com.sun.corba.ee.impl.encoding.CDRInputStream_1_0 read_value
ADVERTENCIA: "IOP00810211: (MARSHAL) Exception from readValue on ValueHandler in CDRInputStream"
org.omg.CORBA.MARSHAL: vmcid: SUN minor code: 211 completed: Maybe
at com.sun.corba.ee.impl.logging.ORBUtilSystemException.valuehandlerReadException(ORBUtilSystemException.java:7053)
Caused by: java.io.IOException: Mismatched serialization UIDs : Source (Rep. IDRMI:com.syskonic.gesplan.entities.ModuloEntity:6D06A8C14D488FFF:8E6FC8687EA9E512) = 8E6FC8687EA9E512 whereas Target (Rep. ID RMI:com.syskonic.gesplan.entities.ModuloEntity:1C6925798CDFD3DF:3455DBF4457AE337) = 3455DBF4457AE337
at com.sun.corba.ee.impl.util.RepositoryId.useFullValueDescription(RepositoryId.java:573)
If I look the server log, I can see that the call has not been produced, it doesn´t show any exception. It looks that the object managed by the server and the remote client aren´t the same and the corba service doesn´t work when remote client call session method. If I change the ModuloEntity and remove the fetch attribute then all this process executes correctly. The problem is in this attribute.
NOTE: I am using the javaagent command line argument.
Hayken

Facing problem with lazy loading in ejb3.0

The following error is coming up when i try to access the collection in the entity entity bean. i am using entitymanager.find() to retrieve the entity. intial set of values are coming fine but when try to access the collection in the entity the error is coming up. one solution is to make the fetch type=eager. but can we do lazy loading with out any problem. the following is the error. kindly help me in this. do i need to do anything extra that mean have to add any annotations or anything.
org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: com.lucid.erp.entities.EmployeeDTO.addresses, no session or session was closed
     at org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationException(AbstractPersistentCollection.java:358)
     at org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationExceptionIfNotConnected(AbstractPersistentCollection.java:350)
     at org.hibernate.collection.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:343)
     at org.hibernate.collection.AbstractPersistentCollection.read(AbstractPersistentCollection.java:86)
     at org.hibernate.collection.PersistentBag.get(PersistentBag.java:422)
     at com.lucidlabs.erp.actions.EmployeeAction.view(EmployeeAction.java:20)
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
     at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
     at java.lang.reflect.Method.invoke(Unknown Source)
     at com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:404)
     at com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:267)
     at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:229)
     at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:221)
     at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:86)
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     at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:221)
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     at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:48)
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     at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:221)
     at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:123)
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     at com.opensymphony.xwork2.DefaultActionInvocation$2.doProfiling(DefaultActionInvocation.java:223)
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this is transactions 101 material. Do you know about transactions and how they work? Do you know about managed entities?
The problem you are having is that the addresses are accessed outside of the transaction in which the entity was fetched. That means there is no more database session and thus the lazy fetch cannot work. If you really need the addresses, you can at least force fetch them by calling getAddresses().size() right after you fetch the entity from the database; assuming that the transaction is still active at that point.

Lazy Loading, Muse, and Scripts

Hi, I'm trying to integrate Lazy loading with Muse in a Web Site.
I would like know if anyone has a better workflow...
So, first I uploaded to the server the "lazy loading content"
http://dandalo.net/teste/lazy-patricia/lazy-pat.html
Then, in Muse, I inserted the html from the page source that I had uploaded.
http://dandalo.net/teste/export-muse/detalhes-old.html
But it didn't work... : (
So...
I have started looking at the html code that Muse created and fond this special phrase... 
Then, I tried this:
Coping the scripts from the "lazy loading content" page and pasting it after this special line:
http://dandalo.net/teste/export-muse/detalhes.html
And it Worked !!!
PS: The java scrips should be in root folder, not in the Scripts folder that Muse created
Does anyone have any tip or workflow not to have to edit the html file to add these script lines?

Hi
Do you have the link to the "lazy loading content"?
I can't find a proper way to do it.
Thanks

Lazy loading in blazeds

Hi ,
Can anyone tell me how to have support for lazy loading with blazeds.I am not using hibernate etc on server side only jboss and ejbs to acess DB.

Hi Maitrey,
dpHibernate is an external project, that solves this common problem.
http://code.google.com/p/dphibernate/
Best regards,
Sd.Plox

Flex Lazy Loading Tree example posted

Hi, all;
I've posted a new example to my blog:
http://flexdiary.blogspot.com/2009/01/lazy-loading-tree-example-file-posted.html
This example demonstrates
- Using lazy loading with a Tree component.
- Using an interface rather than a concrete type to allow the
LazyDataDescriptor to work with any class that implements
LazyLoading.
- An all-actionscript remoting connection
It also has the PHP files and instructions for creating the
mySQL database
that provide the service data.

"danger42" <[email protected]> wrote in
message
news:gkig47$hqu$[email protected]..
> Very cool!
Thanks :-)

It seems you cannot clone objects with attributes using lazy loading in JPA

I have an entity with an attribute using lazy loading:
@Entity
public class B {
@ManyToOne(fetch=FetchType.LAZY)
private A a;
@Entity
public class A {
Assume the following code:
A a1 = new A();
A a2 = new A();
B b1 = EntityManager.find(B.class, ...);
b1.setA(a1);
B b2 = b1.clone();
b2.setA(a2);
Now with lazy loading enabled I get b1.getA() == a2 instead of b1.getA() == a1. Moreover, the debugger displays the same value holder in b1 and b2 for the attribute a. It appears as if cloning does not make a (deep) copy of the value holder managing the attribute a.
How can I create a copy b2 of b1, such that the value holder managing a in b1 is a different object as the value holder managing a in b2?
Thanks, Thomas.

I have filed a bug to have this addressed in Oracle TopLink 11gR1. I would recommend you file a bug against TopLink Essentials in GlassFish or if you have a support contract report the issue to metalink to have the issue resolved.
If this is urgent I did try fixing the issue with a small helper method using some reflection. This method is simplified through its throwing of Exception. If you wish to use something like this I would recommend proper error handling.
     * Helper method for cloning an entity and fixing the woven value-holders to
     * complete a proper shallow cloning.
    public static Employee clone(Employee entity) throws Exception {
       Employee clone = entity.clone();
       // Now fix the cloned ValueHolder references
       Field[] fields = entity.getClass().getDeclaredFields();
       for (int index = 0; index < fields.length; index++) {
           Field field = fields[index];
           if (field.getName().startsWith("_toplink_")) {
               field.setAccessible(true);
               ValueHolderInterface vhi = (ValueHolderInterface)field.get(entity);
               Object value = vhi.isInstantiated() ? vhi.getValue() : null;
               field.set(clone, new ValueHolder(value));
       return clone;
    }Doug

Configuring Lazy Loading on Finder Methods with Annotations

Hi!
I would like to ask you if it is possible to "Configuring Lazy Loading on Finder Methods with Annotations" in Toplink Essentials, using annotations instead of deployment descriptor.
Thank you,
Florin

I am not sure what you are asking. Lazy loading is configured on the mapping, not the queries.
There are examples on how to configure lazy loading on mappings at www.otn.oracle.com/jpa. If this is not what youare trying to do, please give me a use case that you are trying to support. thanks
Peter

Problem with module lazy loading in flex 3

Hi every body!
I have some problems with Module lazy loading. I am using flex 3.5, Module-flex3-0.14, parsley 3.2.
I can't get the LazyModuleLoadPolicy working correctly.
In my main application (the one that loads the modules), my parsley context is the following:
        <cairngorm:LazyModuleLoadPolicy objectId="lazyLoadPolicy" type="{ OpenViewMessage }" />
     <cairngorm:ModuleMessageInterceptor type="{ OpenViewMessage }"/>
     <cairngorm:ParsleyModuleDescriptor objectId="test"
          url="TestModule.swf"
          applicationDomain="{ClassInfo.currentDomain}"
     />
And to load my module:
[Inject(id="test")]
[Bindable] public var test:IModuleManager;
<core:LazyModulePod
     id="moduleLoader"
     moduleManager="{test}"
     moduleId="testModule"
/>
with LazyModulePod.mxml:
<mx:Canvas
    xmlns:mx="http://www.adobe.com/2006/mxml"
    xmlns:module="com.adobe.cairngorm.module.*"
    xmlns:parsley="http://www.spicefactory.org/parsley">
    <mx:Script>
        <![CDATA[
            import com.adobe.cairngorm.module.ILoadPolicy;
            import com.adobe.cairngorm.module.IModuleManager;
            [Bindable]
            public var moduleId:String;
            [Bindable]
            public var moduleManager:IModuleManager;
            [Bindable]
            [Inject(id="lazyLoadPolicy")]
            public var lazyLoadPolicy:ILoadPolicy;
        ]]>
    </mx:Script>
    <parsley:Configure/>
    <module:ViewLoader id="moduleLoader"
        moduleId="{ moduleId }"
        moduleManager="{ moduleManager }"
        loadPolicy="{lazyLoadPolicy}">
         
    </module:ViewLoader>
</mx:Canvas>
OpenViewMessage.as in a swc:
public class OpenViewMessage
        private var _moduleId:String;
        private var _viewId:String;
        public function OpenViewMessage(moduleId:String, viewId:String)
            this._moduleId = moduleId;
            this._viewId = viewId;
        public function get viewId():String{
            return _viewId;
        [ModuleId]
        public function get moduleId():String
            return _moduleId;
In another flex project, my module context is:
<mx:Object
     xmlns:mx="http://www.adobe.com/2006/mxml"
     xmlns:controler="com.cegedim.myit.controler.*">
     <controler:WindowControler/>
</mx:Object>
The module implements IParsleyModule
<mx:Module xmlns:mx="http://www.adobe.com/2006/mxml" layout="vertical"
     implements="com.adobe.cairngorm.module.IParsleyModule"
     xmlns:spicefactory="http://www.spicefactory.org/parsley">
     <mx:Script>
          <![CDATA[
               import org.spicefactory.parsley.flex.FlexContextBuilder;
               import com.adobe.cairngorm.module.IParsleyModule;
               public function get contextBuilder():ContextBuilderTag
                return contextBuilderTag;
          ]]>
     </mx:Script>
     <spicefactory:ContextBuilder id="contextBuilderTag" config="{ MyITTestModuleContext }"/>
     <spicefactory:Configure/>
</mx:Module>
and the WindowControler:
public class WindowControler
     public function WindowControler(){}
     [Init]
        public function initialize():void
            Alert.show("Module Initialized");
        [MessageHandler(scope="local")]
        public function openViewMessageHandler(message:OpenViewMessage):void
            Alert.show("Opening view " + message.viewId + " in the module " + message.moduleId);
If i uncomment the basicLoadPolicy in LazyModulePod.mxml and remove the lazyModuleLoadPolicy, everything works fine. The module is loaded when it's added to stage and it receives correctly messages dispatched to it. But with the lazy policy the module never loads.
I may have missed something or there is somthing i don't understand because i tried the ModuleTest provided in example in cairngorm sources. It works fine (i mean loading the moduleA2 when receiving a message), but if i replace the change the lazyModulePolicy to listen to broadcasted messages instead of a pingMessage, the module never loads too.
    <cairngorm:LazyModuleLoadPolicy objectId="lazyLoadPolicy" type="{ BroadcastMessage }" />
    <cairngorm:ModuleMessageInterceptor
        type="{ BroadcastMessage }" moduleRef="moduleA" />
public class BroadcastMessage
    public function BroadcastMessage()
If someone has any clue, i'll be happy to test it =)
Thanks.

Hello, back on my issue, i tested a little bit more the message dispaching.
I read the lazyLoadPolicy class and noticed that it always has to have a ModuleId property in the message to work, that's why the broadcast message didn't work to awake the module with the lazy loading policy.
So i added copy of my module:
     <cairngorm:ParsleyModuleDescriptor objectId="test"
          url="TestModule.swf"
          applicationDomain="{ClassInfo.currentDomain}"
     />
     <cairngorm:ParsleyModuleDescriptor objectId="testbis"
          url="TestModuleBis.swf"
          applicationDomain="{ClassInfo.currentDomain}"
     />
Set them both with a basicLoadPolicy, and tries to dispatch a message to only one of them using the ModuleId metatag. I then noticed that both modules received the message and not only the one i expected.
I then changed the ModuleMessageInterceptor configuration to dispatch to only one kind of module:
<cairngorm:ModuleMessageInterceptor type="{ OpenViewMessage }" moduleRef="test"/>
and this worked as expected. Only the first module catched the message. I am obiously messing with the ModuleId metatag but i cannot see what's wrong...
I compiled with
-keep-as3-metadata+=ModuleId
but this hasn't changed anything...

Serializing an entity with lazy loaded relationships

Cross-posted from http://forum.java.sun.com/thread.jspa?threadID=793605
Started to think I posted to the wrong forum.
Is it possible to use FetchType.LAZY when sending an entity (let's say Person) to a remote client? I'm fine with the fact that a call like person.getAddress() would have to return null or throw an exception of some sort. But, is it possible to even send the Person object when using lazy fetching?

I have tried, unsuccessfully. The reason I posted this question is that I don't have the experience to know if my failure is due to the goal being impossible or just do to a mistake I made. So, telling me to try doesn't help answer my question. So let me restate...
Can YOU serialize an entity (sending it to a remote client) even though the entity has lazy-loaded relationships? I know that I cannot.
Everything I have read implies that it is possible. However, I have been unable to pull this off using NB 5.5 and the Sun App Serv 9.0. If I make the relationships FetchType.EAGER, everything works. Using FetchType.LAZY, I can't even send the entity to the client, EVEN IF the client doesn't do anything with the entity.

Lazy loading, EntityManager and concurrency.

I need advice which strategy to use with lazy loading.
My project is based on Spring, Struts 2 and Hibernate JPA. I have enough OneToMany and ManyToMany relationships and it's reasonable to use lazy loading. It seems very convenient to load data in Struts Actions with OpenEntityManagerInViewFilter in such way like:
Style style = user.getStyle()
But to avoid LazyLoadException I have to use:
@PersistenceContext(type=PersistenceContextType.EXTENDED)
Unfortunately, EntityManager in this case becomes not thread-safe, according to Spring docs: "+Extended EntityManagers are not thread-safe, hence they must not be used in concurrently accessed beans (which Spring-managed singletons usually are).+" EXTENDED means that EntityManager is shared in user session and my EntityManager is injected in singleton services.
I've found this issue when tried to make quick sequential page reloading which call some selects and got:
java.sql.SQLException: You can't operate on a closed Statement!!!
What's the best practice in this situation:
1. Try synchronize session access to EntityManager by myself or put each user database requests in separate queue (something terrible I suppose).
2. Use HQL queries with join fetch to preload data for access outside of transaction (maybe overhead).
3. Or something else???
And why we need EXTENDED context if it's so unreliable??
Thanks for help!

Hi
Do you have the link to the "lazy loading content"?
I can't find a proper way to do it.
Thanks

Toplink.weaving=true gives PersistenceException; for Lazy Loading config.

I could use some help configuring my persistence.xml file, trying to make sure Lazy loading is configured properly. What I see in the logs normally is that Toplink defaults to Eager fetching on my JPA objects. So according to
http://www.oracle.com/technology/products/ias/toplink/JPA/essentials/toplink-jpa-extensions.html
I need to set toplink.weaving=true in persistence.xml, however I get the Exception below when I make the call to get the EntityManager for the first time.
I'm using OC4J standalone 10.1.3.3 with JDK 1.5.0_13 and the latest Toplink (as you can see in the stack trace below). An excerpt from my persistence.xml is below that.
Caused by: Exception [TOPLINK-30005] (Oracle TopLink Essentials - 2.0 (Build b58g-fcs (09/07/2007))): oracle.toplink.essentials.exceptions.PersistenceUnitLoadingException
Exception Description: An exception was thrown while searching for persistence archives with ClassLoader: xyx-dal-webservice.root:0.0.0
Internal Exception: javax.persistence.PersistenceException: Exception [TOPLINK-28020] (Oracle TopLink Essentials - 2.0 (Build b58g-fcs (09/07/2007))): oracle.toplink.essentials.exc
eptions.EntityManagerSetupException
Exception Description: Value [true] for the property [toplink.weaving] is incorrect when global instrumentation is null, value should either be null or false. at oracle.toplink.essentials.exceptions.PersistenceUnitLoadingException.exceptionSearchingForPersistenceResources(PersistenceUnitLoadingException.java:143)
at oracle.toplink.essentials.ejb.cmp3.EntityManagerFactoryProvider.createEntityManagerFactory(EntityManagerFactoryProvider.java:169)
at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:59)
at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:48)
at gov.dhs.visit.ident.dal.jpa.entity.cvt.util.EntityManagerHelper.<clinit>(EntityManagerHelper.java:20)
... 43 more
Caused by: javax.persistence.PersistenceException: Exception [TOPLINK-28020] (Oracle TopLink Essentials - 2.0 (Build b58g-fcs (09/07/2007))): oracle.toplink.essentials.exceptions.E
ntityManagerSetupException
Exception Description: Value [true] for the property [toplink.weaving] is incorrect when global instrumentation is null, value should either be null or false.
at oracle.toplink.essentials.internal.ejb.cmp3.JavaSECMPInitializer.callPredeploy(JavaSECMPInitializer.java:151)
at oracle.toplink.essentials.internal.ejb.cmp3.JavaSECMPInitializer.initPersistenceUnits(JavaSECMPInitializer.java:239)
at oracle.toplink.essentials.internal.ejb.cmp3.JavaSECMPInitializer.initialize(JavaSECMPInitializer.java:255)
at oracle.toplink.essentials.ejb.cmp3.EntityManagerFactoryProvider.createEntityManagerFactory(EntityManagerFactoryProvider.java:155)
... 46 more
Caused by: Exception [TOPLINK-28020] (Oracle TopLink Essentials - 2.0 (Build b58g-fcs (09/07/2007))): oracle.toplink.essentials.exceptions.EntityManagerSetupException
Exception Description: Value [true] for the property [toplink.weaving] is incorrect when global instrumentation is null, value should either be null or false.
at oracle.toplink.essentials.exceptions.EntityManagerSetupException.wrongWeavingPropertyValue(EntityManagerSetupException.java:244)
... 50 more
SEVERE: Caught exception while handling request: oracle.oc4j.rmi.OracleRemoteException: java.lang.ExceptionInInitializerError; nested exception is:
java.lang.ExceptionInInitializerError oracle.oc4j.rmi.OracleRemoteException: java.lang.ExceptionInInitializerError; nested exception is:
java.lang.ExceptionInInitializerError
persistence.xml
<persistence-unit name="PUName" transaction-type="JTA">
     <provider>oracle.toplink.essentials.PersistenceProvider</provider>
          <jta-data-source>jdbc/mydb</jta-data-source>
<class>....a whole lotta JPA classes...</class>
    <properties>
         <property name="toplink.logging.level" value="FINE" />
         <property name="toplink.logging.timestamp" value="true"/>
           <property name="toplink.target-database" value="Oracle"/>
           <property name="toplink.target-server" value="OC4J_10_1_3" />
           <property name="toplink.weaving" value="true"/>
                <property name="toplink.cache.shared.default" value="false"/>
    </properties>
</persistence-unit>

This error confuses me...
Exception [TOPLINK-30005] (Oracle TopLink Essentials - 2.0 (Build b58g-fcs (09/07/2007))): oracle.toplink.essentials.exceptions.PersistenceUnitLoadingException
Exception Description: An exception was thrown while searching for persistence archives with ClassLoader: sun.misc.Launcher$AppClassLoader@11b86e7
Internal Exception: javax.persistence.PersistenceException: Exception [TOPLINK-28020] (Oracle TopLink Essentials - 2.0 (Build b58g-fcs (09/07/2007))): oracle.toplink.essentials.exceptions.EntityManagerSetupException
Exception Description: Value [true] for the property [toplink.weaving] is incorrect when global instrumentation is null, value should either be null or false.
     at oracle.toplink.essentials.exceptions.PersistenceUnitLoadingException.exceptionSearchingForPersistenceResources(PersistenceUnitLoadingException.java:143)
     at oracle.toplink.essentials.ejb.cmp3.EntityManagerFactoryProvider.createEntityManagerFactory(EntityManagerFactoryProvider.java:169)
     at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:110)I'm using TopLink from regular ol' Java SE (not container managed environment).
http://www.oracle.com/technology/products/ias/toplink/JPA/essentials/toplink-jpa-extensions.html gives some hints, though, especially if you're operating outside of a container (seems like you gotta weave yourself). See http://www.oracle.com/technology/products/ias/toplink/JPA/essentials/toplink-jpa-extensions.html#LazyLoading
Seems the command-line arg "-javaagent:toplink-essentials-agent.jar" is critical if you're running outside a container.

JPA lazy loading with Firebirdsql

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