I didn't try, but I'm sure that if you set a Key field that doesn't exist in the datastore, it will be stored with the key you wanted. If I recall, store only auto assign a key when the key field is null or doesn't exist.
@Key private long id; Christian On Mon, Apr 26, 2010 at 7:59 AM, David Sowerby <[email protected]>wrote: > Hi Christian > > That's interesting ... > > I just felt that I wanted to manage the references (keys) myself, so I > could have more control over when and how those references are > instantiated - Twig seems to do that for you (great in many ways), but > I have some situations with my application where I think that could > have a performance impact - I cannot be sure yet, but I wanted to play > safe on that. > > The single developer question is tricky - I suppose it is more risky > (he might want a holiday one day!), but on the other hand it is open > source. > > On Apr 25, 1:29 pm, Christian Goudreau <[email protected]> > wrote: > > I have one question in mind after reading what you wrote, in wich way you > > have better control in Objectify than Twig ? I'm interested since I moved > > from Objectify to Twig and didn't end up in that situation, yet. > > > > For the cons of only one Developper, he may be alone, but he answer every > > single one question asked in his mailing list, though righ now he's in > only > > for two weeks. And he works really fast, bug fix are often done in less > than > > two days. > > > > Christian > > > > On Sun, Apr 25, 2010 at 5:11 AM, David Sowerby <[email protected] > >wrote: > > > > > > > > > hi jbdhl > > > > > I wish there was an easy answer too - but I suppose at least we have > > > choice! > > > > > My experience, which I hope will at least help you a bit .... > > > > > For back ground .... I am transferring a prototype developed using a > > > db4o back end, but had little done for the UI. There are a lot of > > > relationships in the domain layer, and the design was very much OO not > > > RDBMS > > > > > I started by using JDO thinking it would give me portability. I got > > > it to work, but seemed to end up with some messy code. To be fair, > > > that in part was due to my lack of real understanding of GAE, but I > > > didn't really feel I had achieved portability either - there would > > > still have been changes to make to move elsewhere > > > > > I therefore abandoned the idea of portability, accepting that I would > > > probably have to re-write the Dao layer anyway, if ever I want to > > > move. I decided that it would be better to spend more time on getting > > > that Dao layer isolated and independent - that would give me > > > reasonable portability without compromising the different strengths of > > > different persistent platforms. > > > > > I tried Twig - it seemed a good solution, and was certainly easy to > > > set up and use. I found the documentation is bit sparse on property > > > translators, but otherwise I had no real problems. The amount which > > > Twig takes away from you is one of those classic blessing/curse > > > situations - it is a blessing not to have to think about some of the > > > detail, but you lose control. I felt that once I had understood GAE, > > > I may be losing some of benefits by not having enough direct control - > > > for this application. I would certainly consider Twig again for other > > > applications. > > > > > So I have now migrated to Objectify, which seems fairly > > > straightforward, and I have the level of control I was looking for - > > > with a particular eye on performance since I do not yet have any idea > > > how my application will perform > > > > > I'm afraid the Twig-Objectify discussions occasionally get a bit like > > > a religious argument, which is a shame because they have both done a > > > great job, but with different approaches - and why not? They serve > > > different needs. > > > > > You have probably read this already but I found this tremendously > > > useful to understand GAE, which in turn helped me understand the > > > choices I was trying to make (the Objectify reference isn't a plug - > > > it is just a very well written article) > > > > >http://code.google.com/p/objectify-appengine/wiki/Concepts > > > > > Good luck - it would be interesting to know what you decide in the > > > end ... > > > > > On Apr 25, 5:42 am, bufferings <[email protected]> wrote: > > > > Hi > > > > > > I like Slim3.http://sites.google.com/site/slim3appengine/ > > > > > > -- > > > > 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]<google-appengine-java%[email protected]> > <google-appengine-java%[email protected]<google-appengine-java%[email protected]> > > > > > . > > > > For more options, visit this group athttp:// > > > groups.google.com/group/google-appengine-java?hl=en. > > > > > -- > > > 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]<google-appengine-java%[email protected]> > <google-appengine-java%[email protected]<google-appengine-java%[email protected]> > > > > > . > > > For more options, visit this group at > > >http://groups.google.com/group/google-appengine-java?hl=en. > > > > -- > > 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]<google-appengine-java%[email protected]> > . > > For more options, visit this group athttp:// > groups.google.com/group/google-appengine-java?hl=en. > > -- > 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]<google-appengine-java%[email protected]> > . > For more options, visit this group at > http://groups.google.com/group/google-appengine-java?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. 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