google app engine - how to retry/recover from a java.sql.SQLexception: Concurrent Modification -


Using JDO on GAO, I am using a simple database transaction code block as below.

Is there a good way to try again - throws java.sql.SQLException: concurrent amendment?

Private Ultimate Provider pmp; ...

Persistence Manager pm = pmp.get (); Try {pm.currentTransaction (). Start ();

MyObject myObject = pm.getObjectById (MyObject.class, id);

pm.currentTransaction (). Commit ();

} Finally {

if (pm.currentTransaction () .isActive ()) {log .severe (this.getClass (). GetName () + "database exception caught up . "); Pm.currentTransaction () rollback () .; }}

Has that exception actually been thrown away? Are you sure about the words of Committed () and Active ()?

My second assumption is that this is a singleton bean used together and all of them in the same transaction, with the other questions, finally their requested object.


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