unable to add objects to saved collection in GAE using JDO

Posted by Jeffrey Chee on Stack Overflow See other posts from Stack Overflow or by Jeffrey Chee
Published on 2010-04-09T08:17:34Z Indexed on 2010/04/09 8:33 UTC
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Filed under:

google-app-engine

|

jdo

|

java

I have a ClassA containing an ArrayList of another ClassB

I can save a new instance of ClassA with ClassB instances also saved using JDO. However, When I retrieve the instance of Class A, I try to do like the below:

ClassA instance = PMF.get().getPersistenceManager().GetObjectByID( someid );
instance.GetClassBArrayList().add( new ClassB(...) );

I get an Exception like the below: Uncaught exception from servlet com.google.appengine.api.datastore.DatastoreNeedIndexException: no matching index found..

So I was wondering, Is it possible to add a new item to the previously saved collection? Or was it something I missed out.

Best Regards

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