Hello, I was experiencing problems very similar to the ones described in this thread: http://groups.google.com/group/google-appengine-java/browse_thread/thread/13473fcae300d845 where updates I made on my JDO objects weren't actually reflected in the datastore. Taking the advice of an answer from that thread, I tried closing and reopening the PersistenceManager in the following order:
Initialize pm Retrieve the parent object from the datastore using pm Retrieve the list of child objects from the parent object (with a simple method call) Close pm Re-initialize pm Add a new child object to the list Make the parent object persistent using pm This actually works perfectly, as opposed to when the close and re- initialization of pm are omitted, in which case the parent object's list will not include the newly added child. However, because of this closing of pm, I cannot put this entire update into a single transaction, or an JDOUserException is thrown that tells me 'transaction is still active. You should always close your transactions correctly using commit() or rollback()'. Everything works fine if I separate this code into two transactions, but then it is possible that two users interleave transactions such that they each retrieve identical child lists from the same parent object, each add a new child to that list, and the last to write will wipe out the child added by the first. Any ideas or workarounds would be greatly appreciated! Thanks, Greg -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
