[appengine-java] Re: JDO/JPA Snippets That Work: Change of venue!
Hi Scott, I'm sorry to hear you're struggling to remove a child object from the owner's collection. This message board, our official documentation, the collection of test cases for our JDO/JPA implementation, and the GAE persistence blog are currently the best resources for information about JDO/JPA on app engine. Have you started a thread on the forum describing your problem? If not, please do, and be sure to include your model objects and your persistence code. Thanks, Max On Tue, Oct 27, 2009 at 6:07 AM, stanlick wrote: > > Hey Max -- > > Do you know of a resource (site, book, etc) where I could learn how > owned parent/child collections work vis-a-vis lazy loading and object > identity via overriding equals method in child class? I am having a > difficult time removing a child object from the owner's collection > even though I have implemented an equals method in the child type. > > I can break the code at getFriends().remove(aFriend) and see the > "aFriend" in the collection, however, the remove(...) returns false > and the collection remains the same. This attempt is nested inside > beingTx and commit so I am really perplexed! I have spent more time > with this seemingly trivial use case than it would have taken to > completely write the code by hand in JDBC - and that is a sad > commentary. > > P.S. I read how JDO is so cool and persistence works through > reachability and is transparent. However, I can't seem to get things > to work after hitting the object with a baseball bat! > > Peace, > Scott > > On Oct 16, 6:22 pm, Max Ross > > > wrote: > > Hi everybody, > > > > I've been writing JDO/JPA Snippets That Work for 5 weeks now. I'm > enjoying > > the writing and I'm pleased with the discussion that has taken place > around > > the weekly topics, so I intend to keep going. However, while the Google > > Group is certainly a great place for you, our customers, to reach out to > us > > and to help one another, I'm not convinced it's the best place for me to > be > > publishing something like Snippets That Work. It's not documentation, > but > > it's _almost_ documentation. So, in the interest of consolidating these > > posts in one place I've decided to establish a GAE/J persistence blog: > > > > http://gae-java-persistence.blogspot.com/ > > > > You'll notice I've already cross-posted the first 5 Snippets That Work to > > this blog, and starting next week I'll be posting the new entries there. > If > > you find Snippets That Work valuable I'd recommend subscribing using your > > favorite feed reader, but I'll still send out a link on this message > board > > whenever there is a new post. > > > > Thanks for reading! > > > > Max > > > --~--~-~--~~~---~--~~ 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: JDO/JPA Snippets That Work: Change of venue!
Hey Max -- Do you know of a resource (site, book, etc) where I could learn how owned parent/child collections work vis-a-vis lazy loading and object identity via overriding equals method in child class? I am having a difficult time removing a child object from the owner's collection even though I have implemented an equals method in the child type. I can break the code at getFriends().remove(aFriend) and see the "aFriend" in the collection, however, the remove(...) returns false and the collection remains the same. This attempt is nested inside beingTx and commit so I am really perplexed! I have spent more time with this seemingly trivial use case than it would have taken to completely write the code by hand in JDBC - and that is a sad commentary. P.S. I read how JDO is so cool and persistence works through reachability and is transparent. However, I can't seem to get things to work after hitting the object with a baseball bat! Peace, Scott On Oct 16, 6:22 pm, Max Ross wrote: > Hi everybody, > > I've been writing JDO/JPA Snippets That Work for 5 weeks now. I'm enjoying > the writing and I'm pleased with the discussion that has taken place around > the weekly topics, so I intend to keep going. However, while the Google > Group is certainly a great place for you, our customers, to reach out to us > and to help one another, I'm not convinced it's the best place for me to be > publishing something like Snippets That Work. It's not documentation, but > it's _almost_ documentation. So, in the interest of consolidating these > posts in one place I've decided to establish a GAE/J persistence blog: > > http://gae-java-persistence.blogspot.com/ > > You'll notice I've already cross-posted the first 5 Snippets That Work to > this blog, and starting next week I'll be posting the new entries there. If > you find Snippets That Work valuable I'd recommend subscribing using your > favorite feed reader, but I'll still send out a link on this message board > whenever there is a new post. > > Thanks for reading! > > Max --~--~-~--~~~---~--~~ 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: JDO/JPA Snippets That Work: Change of venue!
Thanks for the lead Jason! I didn't know that page was there. Jorge Gonzalez On Oct 20, 12:25 pm, "Jason (Google)" wrote: > Hi Jorge. Have you seen the App Engine Cookbook? Users are free to post and > search for code snippets:http://appengine-cookbook.appspot.com/ > > - Jason > > On Sat, Oct 17, 2009 at 5:26 AM, Jorge wrote: > > > Thanks Max for sharing your experience and conclusions about this > > *important* topic. > > > I wish there were more places where to find how-to examples about GAE! > > > Jorge Gonzalez > > > On Oct 16, 6:22 pm, Max Ross > > > > > wrote: > > > Hi everybody, > > > > I've been writing JDO/JPA Snippets That Work for 5 weeks now. I'm > > enjoying > > > the writing and I'm pleased with the discussion that has taken place > > around > > > the weekly topics, so I intend to keep going. However, while the Google > > > Group is certainly a great place for you, our customers, to reach out to > > us > > > and to help one another, I'm not convinced it's the best place for me to > > be > > > publishing something like Snippets That Work. It's not documentation, > > but > > > it's _almost_ documentation. So, in the interest of consolidating these > > > posts in one place I've decided to establish a GAE/J persistence blog: > > > >http://gae-java-persistence.blogspot.com/ > > > > You'll notice I've already cross-posted the first 5 Snippets That Work to > > > this blog, and starting next week I'll be posting the new entries there. > > If > > > you find Snippets That Work valuable I'd recommend subscribing using your > > > favorite feed reader, but I'll still send out a link on this message > > board > > > whenever there is a new post. > > > > Thanks for reading! > > > > Max --~--~-~--~~~---~--~~ 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: JDO/JPA Snippets That Work: Change of venue!
Hi Jorge. Have you seen the App Engine Cookbook? Users are free to post and search for code snippets: http://appengine-cookbook.appspot.com/ - Jason On Sat, Oct 17, 2009 at 5:26 AM, Jorge wrote: > > Thanks Max for sharing your experience and conclusions about this > *important* topic. > > I wish there were more places where to find how-to examples about GAE! > > Jorge Gonzalez > > > On Oct 16, 6:22 pm, Max Ross > > > wrote: > > Hi everybody, > > > > I've been writing JDO/JPA Snippets That Work for 5 weeks now. I'm > enjoying > > the writing and I'm pleased with the discussion that has taken place > around > > the weekly topics, so I intend to keep going. However, while the Google > > Group is certainly a great place for you, our customers, to reach out to > us > > and to help one another, I'm not convinced it's the best place for me to > be > > publishing something like Snippets That Work. It's not documentation, > but > > it's _almost_ documentation. So, in the interest of consolidating these > > posts in one place I've decided to establish a GAE/J persistence blog: > > > > http://gae-java-persistence.blogspot.com/ > > > > You'll notice I've already cross-posted the first 5 Snippets That Work to > > this blog, and starting next week I'll be posting the new entries there. > If > > you find Snippets That Work valuable I'd recommend subscribing using your > > favorite feed reader, but I'll still send out a link on this message > board > > whenever there is a new post. > > > > Thanks for reading! > > > > Max > > > --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
