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 <[EMAIL PROTECTED]> To: [email protected]; [EMAIL PROTECTED] 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 <[EMAIL PROTECTED]> 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<Entry> results = (List<Entry>)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
