[appengine-java] Workflow Engine
Has anyone successfully implemented a Java workflow engine on GAE? (or perhaps considering it). I'm thinking of something like Bonita (http://www.bonitasoft.com/) or Enhydra Shark (http://www.enhydra.org/workflow/shark/index.html) and would welcome feedback from anyone who has tried it -- 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.
[appengine-java] Re: Objectify - Twig - SimpleDS articles
Andreas, first thanks for the article, it was hugely interesting and of course thanks to all who have given us some alternatives to argue about! A few themes seem to come out of this for me 1) Some people are just either happier with what they know (SQL/ RDBMS) - perfectly understandable and probably more productive initially at least, but if someone didn't move the goalposts now and then we would never get any innovative change. 2) Some just have to live with existing code and work with that. That's life I guess. 3) Others see the datastore as a component of a different way of working which overall has some major benefits - making the use of the datastore simple and efficient is just part of the equation. 4) Abstraction is all very well - but if the trade off is a lack of clarity or poor performance then it is in danger of being an objective for its own sake. I don't think anyone has mentioned the famous impedance mis-match between OOP and RDBMS. It seems to me that BigTable is a better match to OOP than an RDBMS is - although I found JDO a struggle. I have the luxury of developing a Java app from scratch, which of course is not the same for everyone. I did get JDO to work but it does feel like I am making life hard for myself by doing so. Now all I have to do is decide which of the alternatives to go for . On Mar 30, 7:33 pm, Jeff Schnitzer wrote: > On Tue, Mar 30, 2010 at 8:03 AM, Guillermo Schwarz > > wrote: > > > SQL can be run on top of a file system (fseek, read, write) or on top of a > > persistent hashmap (datastore). > > > If you create a SQL interface on top of any of those, then it is a > > relational database, not a fake but a real relational database. Why would I > > want a relational database? Consistency, for starters. ACID transactions. > > Set operations. > > ...except that you *can't* actually create a performant relational > database on top of appengine. > > Let's be realistic here. There is one reason and one reason only why > modern RDBMSes can perform at anything remotely like the speeds > necessary for web applications: > > * Lots and lots of RAM, enough to cache whole indexes. > > You don't have this in appengine. You get, at best, somewhere around > 110 megs. How fast do you think an RDBMS is going to perform on a > machine that has been lobotomized to 100 megs of RAM??? If you have > an antique computer from the 1990s you can find out. > > I have no doubt that you can create an RDBMS on top of the GAE > datastore. I also have no doubt that trying to tune a Hibernate app > to run at reasonable speeds will be a nightmare that I never want to > experience. > > Jeff -- 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.
[appengine-java] Re: Error while Using the Datastore with JDO
I usually find I get this when the class I am trying to persist doesn't have the @PersistenceCapable annotation, or more often, where one of its ancestors hasn't. On Apr 9, 6:47 pm, "Ikai L (Google)" wrote: > Can you post the class? > > > > > > On Fri, Apr 9, 2010 at 5:49 AM, Smitha wrote: > > I'm trying to create a JDO object, create a table and assign values to > > it. > > > But I'm getting the following error when i try to run it although I > > have enhanced it and I'm using the Google Plugin for eclipse to build > > it. > > > The class "The class "com.store.db.UserDetails" is not persistable. > > This means that it either hasnt been enhanced, or that the enhanced > > version of the file is not in the CLASSPATH (or is hidden by an > > unenhanced version), or the Meta-Data/annotations for the class are > > not found." is not persistable. This means that it either hasnt been > > enhanced, or that the enhanced version of the file is not in the > > CLASSPATH (or is hidden by an unenhanced version), or the Meta-Data > > for the class is not found. > > RequestURI=/signUser > > > Caused by: > > > org.datanucleus.jdo.exceptions.ClassNotPersistenceCapableException: > > The class "The class "com.store.db.UserDetails" is not persistable. > > This means that it either hasnt been enhanced, or that the enhanced > > version of the file is not in the CLASSPATH (or is hidden by an > > unenhanced version), or the Meta-Data/annotations for the class are > > not found." is not persistable. This means that it either hasnt been > > enhanced, or that the enhanced version of the file is not in the > > CLASSPATH (or is hidden by an unenhanced version), or the Meta-Data > > for the class is not found. > > at > > > org.datanucleus.jdo.NucleusJDOHelper.getJDOExceptionForNucleusException(Nuc > > leusJDOHelper.java: > > 241) > > at > > > org.datanucleus.jdo.JDOPersistenceManager.jdoMakePersistent(JDOPersistenceM > > anager.java: > > 674) > > > Please let me know if you need any more details. > > Thanks in advance. > > Smitha. > > > -- > > 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 > unsubscr...@googlegroups.com> > > . > > For more options, visit this group at > >http://groups.google.com/group/google-appengine-java?hl=en. > > -- > Ikai Lan > Developer Programs Engineer, Google App > Enginehttp://googleappengine.blogspot.com|http://twitter.com/app_engine -- 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.
[appengine-java] Re: Can't decide: JDO, Twig-Persist or Objectify?
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 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 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 > 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 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.
[appengine-java] Re: Can't decide: JDO, Twig-Persist or Objectify?
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 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 > 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 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 > > 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 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. > > T
[appengine-java] Re: App Engine Scalability
This is relevant too http://code.google.com/p/googleappengine/issues/detail?id=2456 On Jun 10, 11:31 pm, Thomas wrote: > Hi: > > Please > seehttp://groups.google.com/group/google-appengine-java/browse_thread/th... > for more detail. -- 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.
[appengine-java] Re: What would you recommend: Objectify or Twig?
This is a difficult question to give a fair answer to - most of us only have time to make a fairly quick assessment then just decide to go with something - which means we only know one of them in any depth. I looked at Twig and Objectify, tried Twig briefly then elected to use Objectify - but that was because I preferred the approach of Objectify for my application, and my way of working and not because I felt there was anything wrong with Twig. I cannot comment on Slim3, I have not tried it. Simon's suggestion above to look at some of the debate threads is still valid I think - it is probably the philosophy which drive your choice. For me it was a case of keeping things simple and transparent in case I run into performance issues. I can say that the Objectify documentation is excellent, and the responses to questions fast and equally good. Twig's documentation was not as thorough when I looked at it but that may have changed, and I do not know what the forum responses are like. On Jun 16, 7:28 pm, Houston startup coder wrote: > I'm liking Slim3 so far. It has a fast wrapper for the low-level API > that does not use reflection (meaning it's even faster than frameworks > that do). Plus it has some basic web framework helpers as well. > > Stephen > > On Jun 16, 12:34 am, nicolas melendez wrote: > > > > > +1 Objectify > > > But give a chance to twig too > > > On Tue, Jun 15, 2010 at 1:56 PM, Dan Billings wrote: > > > +1 Objectify > > > > On Jun 15, 11:25 am, Simon wrote: > > > > There's a big thread athttp:// > > > groups.google.com/group/google-appengine-java/browse_thread/th... > > > > where the authors of the two frameworks discuss the respective > > > > benefits of their frameworks, for different scenarios. It's probably > > > > worth having a read, although it's getting a bit old now. > > > > > Personally I've found Objectify very good - very thorough > > > > documentation and it works for me :) > > > > > On Jun 15, 9:51 am, Marcel Overdijk wrote: > > > > > > What would you recommend: Objectify or Twig? > > > > -- > > > 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 > > unsubscr...@googlegroups.com> > > > . > > > For more options, visit this group at > > >http://groups.google.com/group/google-appengine-java?hl=en. > > > -- > > Nicolás Meléndez > > Java Software Developer > > > 1) Google App Engine works: > > > 1.a)http://www.clasificad.com.ar (Local free classifieds for housing, > > sale, services, local community, curses,jobs, and events - GAE/J + Wicket + > > YUI) > > > 1.b)http://www.chessk.com (Massive multiplayer chess online GAE/J + > > Applets + Wicket) > > > 2) Linkedin:http://ar.linkedin.com/in/nicolasmelendez -- 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.
[appengine-java] Re: Getting a grip on startup
Hi John I'm afraid I cannot offer any specific suggestions, but I it may be worth looking at the Objectify persistence framework, one of its primary goals was to reduce start up time. If nothing else, trawling the documentation may give you some valuable clues On Aug 4, 2:57 am, John wrote: > As our app has grown, the amount of initialization work to do in order to > make an instance useful has increased to the point that GAE often terminates > requests that start a new instance. We had a warmup servlet, but the work > started to commonly exceed the deadline. We're now looking to pare down the > warmup, but we're having trouble with tuning since the behavior seems pretty > different on the dev server from GAE. On the dev server, the initialization > (loading our initial servlets) will complete in the vicinity of 4sec while > GAE instance startup is often more than 20sec. We often see inexplicable > gaps in our logging of 15sec or more (seemingly hung up), but it doesn't > seem repeatable. > > Our focus to date has been to optimize the JDO/Datanucleus startup, but we > believe that a significant contributor might be the number of classes > loaded. Is it accurate to conclude that class loading carries a larger > overhead on GAE than other environments? Are there any tools that will help > us understand the processing during this startup? The Appstats tool shows > long delays, but we don't know what is taking time besides the RPCs. -- 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-java@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.
[appengine-java] Distributed Transactions
There is always a good deal of debate in this group about transactions - but does anyone know what the status is of the design presented by Daniel Wilkerson at Google I/O 2009? There don't seem to have been any recent updates to either of the following: Design explanation at http://danielwilkerson.com/dist-trans-gae.html code (only) posted at http://code.google.com/p/tapioca-orm/ The video of the presentation is at http://code.google.com/events/io/2009/sessions/DesignDistributedTransactionLayerAppEngine.html and seemed great work which could transform the use of app engine. Has it just proved too difficult to implement on the Google infrastructure? -- 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.
[appengine-java] Re: Users management for non-google accounts
Sounds like you want OpenId This may help: http://code.google.com/appengine/docs/java/users/ Extract: Note: The 1.3.4 release includes support for authentication via OpenID as an experimental feature. OpenID allows users to authenticate by supplying a URL that identifies them with an OpenID provider, a service where the user has previously created an account. Because OpenID support is an experimental feature, the API may change in future minor releases of the SDK. Let us know what you think! On Jul 23, 4:09 pm, cghersi wrote: > Good afternoon, > > I'm very new to GAE, and I cannot understand how may I merge the > account management for users having and not having a Google account. > > I would like to have a single sign-in page (google style) where users > with google accounts can type their Google credentials and enter in my > app, while users without google accounts can type their "MyApp- > customized" credentials and enter the same. > > Is it feaseable? > > Or do I have to create my own Users table and replicate the users > accounts for the users provided with Google accounts? > > Thank you very much! > > Bye -- 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.
[appengine-java] Re: Mail Service - get User which belongs to email address
hi Lars Would this help you/ http://code.google.com/appengine/docs/java/users/ On Jul 26, 10:19 pm, vogella wrote: > Hi, > > I have a small Todo application written. I would like to use the Mail > service to receive new todos items via email. > > I can get the sender of the email via getFrom() and would like to map > this to the user in my application and create a new Todo for this > user. > > Is it possible to retrieve the user based on an email from AppEngine? > If yes it would be great if you can give me a pointer where to look. > > Best regards, Lars > > --- > I originally posted this message > tohttp://groups.google.com/group/google-appengine > before realizing that there is a Java specific group. -- 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.
[appengine-java] Re: task queue
Hi Julzin Seems like a popular theme, see: http://groups.google.com/group/google-appengine-java/browse_thread/thread/fbbbab71067d536b On Aug 10, 8:24 am, julzin wrote: > hi, > I would like to know if there was a way to know when a queue is empty > (or when all the tasks that have been assigned to it are finished) ? > From the API documentation, it seems to me like a queue object only > allows to add a task, but not to retrieve this kind of information. > Maybe there is a way through the admin console? > (sorry for my bad english) > thanks, > Sincerely, > Julzin -- 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.
[appengine-java] Re: Inheritance
I am sorry I cannot read Spanish, but inheritance definitely works. On Sep 3, 12:10 am, lisandrodc wrote: > Hi! > Someone has some code working correctly that uses inheritance? Since > in the link: > > http://code.google.com/intl/es/appengine/docs/java/datastore/relation... > He does not say anything in the matter... > > Regards > Lisandro -- 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.
[appengine-java] Re: Inheritance
What is BD? The code you depends on which method of communicating to the datastore you use: JPA, JDO, Objectify, Twig for example. Which have you chosen? On Sep 4, 12:01 am, lisandrodc wrote: > Thanks, David. > If you say that inheritance works to persist in the BD. > Will you have some example in code? > Regards > Lisandro > > On 3 sep, 16:35, David Sowerby wrote: > > > > > I am sorry I cannot read Spanish, but inheritance definitely works. > > > On Sep 3, 12:10 am, lisandrodc wrote: > > > > Hi! > > > Someone has some code working correctly that uses inheritance? Since > > > in the link: > > > >http://code.google.com/intl/es/appengine/docs/java/datastore/relation... > > > He does not say anything in the matter... > > > > Regards > > > Lisandro -- 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.
[appengine-java] Re: Eclipse does not launch after upgrading to gae 1.3.8
Try looking in the Eclipse log file. Usually you will find that in the .metadata directory of your workspace, if not check the notes at http://www.eclipse.org/eclipse/platform-core/documents/3.1/debug.html David On Oct 22, 6:54 pm, Vik wrote: > hie > > I am talking about eclipse ide itself. Here is what happened > > i saw in ide google update is available. i installed the 1.3.8 and at the > end it asked me to restart the ide. I clicked yes. > and then ide closed and spalsh screen appeared for few secs and then closed. > That's it. After that now this is happening whenever i try to launch ide. > > Tried restarting my windows xp as well. eclipse i was using was gallilio > > Thankx and Regards > > Vik > Founderwww.sakshum.comwww.sakshum.blogspot.com > > On Fri, Oct 22, 2010 at 7:17 PM, Nurettin Omer Hamzaoglu < > > > > > > > > nomerhamzao...@gmail.com> wrote: > > You can launch eclipse or launch hosted mode? And what error(s) are > > you getting? > > > On Oct 22, 3:15 pm, Vik wrote: > > > Hie > > > > Today i upgraded to gae 1.3.8 and now i m unable to launch eclipse. > > Please > > > advise > > > > Thankx and Regards > > > > Vik > > > Founderwww.sakshum.comwww.sakshum.blogspot.com > > > -- > > 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 > unsubscr...@googlegroups.com> > > . > > 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 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.
[appengine-java] Re: Just getting started with Datastore
Hi Matt I agree with all that has been said here - the ultimate choice has to be yours to suit your needs, but if I had one single recommendation it would be to read the Objectify documentation to start with - even if you never use Objectify you will have gained a very quick and clear understanding of the datastore, which is likely to be different to anything you have used before. Have fun ... http://code.google.com/p/objectify-appengine/wiki/IntroductionToObjectify David On Jan 31, 5:07 am, Matt Reeves wrote: > Thanks for the feedback. I am willing to try the low-level API first and > that's what I thought I was doing but could not figure out (and am still > confused about) how to initially define data. For example I want to have a > persistent entity with two properties of type string and one numerical > property. When I use this bulkloader tool it is storing all the data as > string, so maybe my problem is just learning how to use this tool to load > data (which I definitely want to do). > > Thanks. -- 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-java@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.
[appengine-java] Re: Just getting started with Datastore
Matt No problem - I think most of us have been there! On Feb 2, 3:17 am, Matt Reeves wrote: > Thanks David (and thanks all), that is a good intro. I think the light bulb > just went off in my head that there is no requirement that you define how an > Entity and its properties should look. Two entities can be of the same kind > but look completely different (which would likely be pointless to have any > useful queries). I was just having a hard time unlocking my brain from the > relational db world... all the explanation was spelled out right in front of > me, just took a few nights to sink in. > > Thanks again. -- 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-java@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.
