Hi, I think the issue will be in the MyRunnable class. You create the MyRunnable instance in the http worker thread, if you simply inject an EntityManager there it'll be the one bound to the current thread (the http worker). After submitting it to a different thread you essentially leak the transaction which can have many side effects (like when the same http worker is selected again, the PersistFilter will try to start a new transaction but it's already open for that thread - held by the long running background job).
The correct way to handle this is to inject a Provider<EntityManager> in MyRunnable and annotate the database using methods with @Transactional. -- L -- L On Wed, May 13, 2015 at 11:58 AM, jbl <[email protected]> wrote: > Hello, > > > I'm relatively new to guice, and I've got a problem that I quite don't > understand. > > I have a webapp based on guice, eclipse link, mysql that runs on a tomcat > 7. The app uses a com.google.inject.persist.jpa.JpaPersistModule and > a com.google.inject.persist.PersistFilter > > For some requests the webapp creates a set of java.lang.Runnable, passes > them to a java.util.concurrent.ExecutorService, and returns. The runnables > are numerous time-consuming jobs that must be executed in background to > avoid blocking the request. Also, each job has to access the EntityManager. > However, the current implementation is quite naive: > > @Inject private Provider<MyRunnable> myRunnableProvider; > @Inject private ExecutorService executorService; > > MyRunnable runnable = myRunnableProvider.get(); > executorService.submit(runnable); > > This code runs fine on my development computer, but I get this exception > when I run it in a production environment : > > java.lang.IllegalStateException: Work already begun on this thread. Looks > like you have called UnitOfWork.begin() twice without a balancing call to > end() in between. > at com.google.common.base.Preconditions.checkState(Preconditions.java: > 150) ~[guava-15.0.jar:na] > at com.google.inject.persist.jpa.JpaPersistService.begin( > JpaPersistService.java:73) ~[guice-persist-4.0.jar:na] > at com.jbl.MyRunnable.run(MyRunnable.java:107) > > I think that this has something to do with the Scope, but I don't quite > understand how to correct this. > > Thank you for any insight on this ! > > -- > You received this message because you are subscribed to the Google Groups > "google-guice" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/google-guice. > To view this discussion on the web visit > https://groups.google.com/d/msgid/google-guice/141ea4f0-3f34-45c9-a8cf-c28779859a2d%40googlegroups.com > <https://groups.google.com/d/msgid/google-guice/141ea4f0-3f34-45c9-a8cf-c28779859a2d%40googlegroups.com?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "google-guice" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/google-guice. To view this discussion on the web visit https://groups.google.com/d/msgid/google-guice/CAD-udUCC6FM2w9wGHNdUcMyZD6FQykHfGpUW%3DNveLu7UTawPkw%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
