I have suggestion for GAE Since it's possible to have multiple versions, why not have a version u set from admin console, which will be switched to automatically during down time
On Feb 2, 5:23 am, Ian Marshall <[email protected]> wrote: > In the GAE/J documentation under "How-To | Handling Scheduled > Maintenance Periods", it states: > > "During this period, all datastore writes and transactions will throw > an exception. Your application can detect these errors and indicate to > the user that the application is in read-only, recommending that they > try again later." > > An example is then given to catch the relevant exception during > PersistenceManager#makePersistent(...), but I cannot find an example > for datastore updates of already-existing entities. > > Does anyone know at what point an update to a persistent entity (not > using PersistenceManager#makePersistent(...)) will result in the > CapabilityDisabledException exception being thrown? For example, where > in the following code extract could I expect this exception? > > // Non-GAE method to return the singleton instance > PersistenceManagerFactory pmf = > DataExchange.getPersistenceManagerFactory(); > > PersistenceManager pm = pmf.getPersistenceManager(); > Transaction tx = pm.currentTransaction(); > > try > { > tx.begin(); > > // Non GAE method to get a detatched instance by its ID > (within the current tx) > Item itemEdit = findItemByID(tx, pidData.loID, > loLoggedOnUserID); > > // Non GAE method to amend the itemEdit instance > itemEdit = updateItemWithPageItemData(tx, itemEdit, pidData, > ipmMode); > > tx.commit(); > } > finally > { > try > { > if (tx.isActive()) // Because of an exception, say > { > tx.rollback(); > } > } > finally > { > pm.close(); > } > } -- 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 [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
