Hi Guys The Entry class is actually an entity I just changed the code to use native query as I was getting the same result using just createQuery. I have attached the Entry.class and the class containing the query (EntryQuery). As you can see in EntryQuery there is various code commented out, this is just where I have tried different things. When I return the list of results and try and display them in a JList with the following code: data = eq.getAll(); jList1.setListData((Vector)data); I get the following exception: java.lang.ClassCastException: org.apache.openjpa.kernel.DelegatingResultList cannot be cast to java.util.Vector at veilig.mainui.VeiligTopComponent.(VeiligTopComponent.java:37) at veilig.mainui.VeiligTopComponent.getDefault(VeiligTopComponent.java:94) at veilig.mainui.VeiligTopComponent$ResolvableHelper.readResolve(VeiligTopComponent.java:149) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at java.io.ObjectStreamClass.invokeReadResolve(ObjectStreamClass.java:1061) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1762) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329) at java.io.ObjectInputStream.readObject(ObjectInputStream.java:351) at org.netbeans.modules.settings.convertors.XMLSettingsSupport$SettingsRecognizer.readSerial(XMLSettingsSupport.java:542) at org.netbeans.modules.settings.convertors.XMLSettingsSupport$SettingsRecognizer.instanceCreate(XMLSettingsSupport.java:574) at org.netbeans.modules.settings.convertors.SerialDataConvertor$SettingsInstance.instanceCreate(SerialDataConvertor.java:415) [catch] at org.netbeans.core.windows.persistence.PersistenceManager.getTopComponentPersistentForID(PersistenceManager.java:513) at org.netbeans.core.windows.persistence.PersistenceManager.getTopComponentForID(PersistenceManager.java:618) at org.netbeans.core.windows.PersistenceHandler.getTopComponentForID(PersistenceHandler.java:422) at org.netbeans.core.windows.PersistenceHandler.load(PersistenceHandler.java:147) at org.netbeans.core.windows.WindowSystemImpl.load(WindowSystemImpl.java:69) at org.netbeans.core.NonGui$3.run(NonGui.java:205) at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209) at java.awt.EventQueue.dispatchEvent(EventQueue.java:597) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:173) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:168) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:160) at java.awt.EventDispatchThread.run(EventDispatchThread.java:121) Any help or guidance is very much appreciated. David Craig L Russell wrote: > Hi David, > > One other thing that occurs to me is whether you're using the native > query appropriately. > > I assume that Entry.class is *not* an Entity. It's just a plain old > Java class with no persistence annotations. > > Perhaps we can help better if you would include your Entity.java and > schema in the message. And the exception with stack trace. > > Regards, > > Craig > > On Jan 22, 2008, at 2:55 AM, David Beer wrote: > >> Hi Patrick >> >> I will be able to get the exact information retruned later when I am >> back home. >> >> I am trying to display a list of the items returned from the query in >> a JList (javax.swing.JList). A JList takes either an array, a >> ListModel or a Vector; I was trying to use a Vectory as I can just >> add elements to it and not worry about memory allocation or the size >> of the Vector being too large. >> >> My point is that when I tried to cast the resulting data from the >> query I got an exception. Cannot Cast Delegate org.apache.openjpa >> >> I will get the exact data this evening when i get home >> >> Thanks >> >> David >> >> ----- Original Message ---- >> From: Patrick Linskey >> To: users@openjpa.apache.org; david.m.beer@btinternet.com >> Sent: Monday, 21 January, 2008 11:52:15 PM >> Subject: Re: Understanding getResultList() >> >> Hi, >> >>> and in return I am seeing a list containing a delegate and a >>> persistence object. >> >> Can you include a printout of the data you see, or some more detailed >> explanation, such as class names of the instances returned? >> >>> display. This is fine with a small amount of records but what about a >>> large amount of records. >> >> Are you concerned about the overhead involved in iterating through a >> result list fully just to copy it over to the Vector? If the framework >> that you are using does not provide any interface-based support, then >> you might not have many options. One idea might be to try to create a >> subclass of Vector that overrides most methods to just return values >> from the actual backing list. >> >> -Patrick >> >> On Jan 21, 2008 3:34 PM, David Beer >> wrote: >>> Hi All >>> >>> I have a n issue with using Query getResultList(), I am executing a >>> nativeQuery("SELECT * FROM ENTRY", Entry.class). And performing the >>> query like so List results = >> (List)query.getResultList(); >>> and in return I am seeing a list containing a delegate and a >>> persistence object. >>> >>> My main problem is that I am trying to display the resulting data >> that >>> comes back in a JList, in order to set the list data on a JList you >> have >>> to have the data in a Vector. So when I tried to cast the List to a >>> Vector I got an exception. >>> >>> When I perform the same query using TopLink I get back a list of >> Objects >>> of the type and no extra information. At the moment I am going >> through >>> the results and getting each Object element and adding to Vector to >>> display. This is fine with a small amount of records but what about a >>> large amount of records. >>> >>> What is the best way of getting back just a list of Objects no >>> additional data? >>> >>> Thanks >>> >>> David >>> >> >> >> >> -- >> Patrick Linskey >> 202 669 5907 >> >> >> >> > > Craig Russell > Architect, Sun Java Enterprise System http://java.sun.com/products/jdo > 408 276-5638 mailto:Craig.Russell@sun.com > P.S. A good JDO? O, Gasp! >