[appengine-java] Re: Task queue not starting the action when expected

Hi, I've experienced the same phenomenon so that I added a new issue for this: http://code.google.com/p/googleappengine/issues/detail?id=2924 Thanks, Kaz On Feb 26, 8:05 am, Jerome wrote: > Hello, > > We have been using task queues for a few months without problem. We > handle actions that mu

[appengine-java] Updating a simple boolean

I'm trying to update a simple boolean value on a collection of objects returned by a query. The objects are being returned, and I set the value on the bean, then persist, but it's not working. What am I missing? The Submission class has a "notifyAfter" as a Long (raw date), and an "isNotified" Bo

[appengine-java] Emails sending from AppEngine (javax.mail) never received on free.fr domain

hi, All emails sent from my App to free.fr domain are never received. I received the following response from their server: "IP 209.85.221.110 is blacklisted for 85775s (too many errors (unexisting recipients, broken connections), rejecting mail)" On other domains, all emails are received. How I ca

[appengine-java] Task Queue Problems

Ok so either I'm doing something really stupid or I can't get a simple task to execute. I have defined a task worker at /tasks/foo. I can hit /tasks/foo no problem and the code executes fine (just a simple servlet of course). The problem is when I add a task to the queue like: queue.add(TaskOpt

[appengine-java] Children in an owned one-to-many relationship not being retrieved, what am I doing wrong?

I have the following 3-part owned relationship... Users, the root entity, have a collection of Decks, as such (I am not including the specific subclass of User as it doesn't seem to be relevant): @PersistenceCapable(identityType = IdentityType.APPLICATION) @Inheritance(strategy = InheritanceStrat

[appengine-java] transaction 'scope', unexpected behaviour

I am seeing some transaction-related behaviour, using JDO and GAE 1.3.1, that puzzles me. I get an exception if I do something like the following. All entities below are in separate entity groups: PersistenceManager pm = PMF.get().getPersistenceManager(); //... fetch entity a1 of kind A, mo

[appengine-java] Re: MemCache development mode persistence

SOLUTION: I wrote it to the Datastore myself using the low-level API. But socket I/O would be nice in the development environment. Steve Pritchard On Mar 6, 12:06 pm, Steve Pritchard wrote: > I was looking for a way to persist my MemCache so I could do > production like testing in development m

[appengine-java] Request was aborted

Hello, I have one chron job that should be triggered every minute once. I have now the problem that about every 5 minutes the following warning occurs. I also notice that the datastore gets stuck sometimes leading to a timeout. The later happens maybe every hour or something once. Ther is really n

[appengine-java] MemCache development mode persistence

I was looking for a way to persist my MemCache so I could do production like testing in development mode to make sure I correctly handle various use cases. I tried writing a file using the technique described in http://groups.google.com/group/google-appengine-java/browse_thread/thread/cdd3abc956

Re: [appengine-java] Re: Best practices for datastore and JDO?

Relational theory, SQL and JDBC are functional specifications and RDBMS vendors implement these specifications. Actually speaking data model has nothing to do with technology. A data model in software engineering is an abstract model

[appengine-java] 1.3.1 Security Fallout

Under 1.2.8 and 1.3.0 I created a SocketLogger that was extremely useful in sending messages to a second machine in my development enviroment so I could easily see what was going on in the AppServer handlers. Previously under Eclipse I put a jar in plugins/version-str/appengine- java-sdk-1.x.x/li

[appengine-java] Re: Should I use JPA or JDO for DataStore?

Since you're a student, and if you have the time, I'd recommend learning JDO for the following reasons: 1. You already know JPA. Might as well learn something new. :) 2. JDO, imo, fits the GAE datastore much better (I think there are quite a few discussions around here as to why). Enjoy! On Mar

[appengine-java] Re: Best practices for datastore and JDO?

I think the gap here is that a RDBMS (PostgreSQL) and the App Engine Datastore are totally different. In fact, I think the latter influences your design much more than the former. The sorts of joins you used to be able to do in your DB to efficiently retrieve data don't work in the GAE datastore.

[appengine-java] Should I use JPA or JDO for DataStore?

Just in cast I want to make use of some existing Java APIs for messing with DataStore, which may be the low-level API would work the best. I just wonder, as I am still a college student, one of my lecturer told me that "we should use JPA (2.0) now as JDO is not the preferred way for persisting dat

[appengine-java] Re: Threads in Java

Then it seems that App Engine is not the tool you want to use for this research. You may try paid services from other vendors, which generally would have more resources available to you. On Mar 6, 10:02 pm, wiilycy wrote: > I am doing a project where I will try to optimize google engine by using

Re: [appengine-java] Threads in Java

I am doing a project where I will try to optimize google engine by using multi-core cpus. So, now i am doing a research how the low API works in order to find out if such an optimization is possible. On Fri, Mar 5, 2010 at 7:20 PM, John Patterson wrote: > Basically each request is a thread in app

Re: [appengine-java] Re: Objectify-Appengine, a typesafe data persistence tier for App Engine

ha ha perhaps you could have designed the API... at least it shows you are thinking along the same lines as the Google Engineers :) On 6 Mar 2010, at 18:01, Nacho Coloma wrote: Nacho, there is already a public DatastoreService.getActiveTransactions() that returns the threads open transaction

[appengine-java] Re: JDO Level2 Cache setup for dummies

> Is it possible that DN L2 caching in GAE drives down CPU milliseconds > used but overall response times get slower? Benefits of an L2 cache are subject to what you're doing (it's benefit is for multiple PM's for a PMF accessing the same objects, and hence providing a "quick" way of accessing the

Re: [appengine-java] Re: Objectify-Appengine, a typesafe data persistence tier for App Engine

> Nacho, there is already a public DatastoreService.getActiveTransactions() > that returns the threads open transactions.  Is this not what you want? > http://code.google.com/appengine/docs/java/javadoc/com/google/appengine/api/datastore/DatastoreService.html#getActiveTransactions() OK, now I am j

Re: [appengine-java] Re: Objectify-Appengine, a typesafe data persistence tier for App Engine

On 6 Mar 2010, at 17:35, Nacho Coloma wrote: -- Nacho. P.S.: hey GAE guys: can you add a datastore.getActiveTransactions() method? We are storing the same info using a redundant ThreadLocal! (GAE is doing the same, just make that information public :) Nacho, there is already a public Datast

Re: [appengine-java] Re: Objectify-Appengine, a typesafe data persistence tier for App Engine

> About this I must disagree.  Everything I've learned about the > appengine datastore says that unless you specifically need > transactions, you should avoid using parent entities. > > When any entity is written, the optimistic concurrency journal is > maintained for the root of the entity group.