Google app engine - what is the lifecycle of PersistenceManager?

Posted by Domchi on Stack Overflow See other posts from Stack Overflow or by Domchi
Published on 2010-01-31T23:02:37Z Indexed on 2010/04/24 16:43 UTC
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google-app-engine

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java

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jdo

What is the preferred way of using GAE datastore PersistenceManager for web app? GAE instructions are a bit ambiguous on the matter.

Do I instantiate PersistenceManagerFactory for each RPC call, or do I use only one factory for all requests? Do I call PMF.get().getPersistenceManager(), or do I call PMF.get().getPersistenceManagerProxy()? Do I close PM after each RPC call, or do I leave it open? What are you guys doing?

Furthermore, I'm not certain how GAE handles 30-second-per-request limit. Is it even possible to reference the same PM between requests?

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