Hi,
Adding @DependsOn("UniversalConfigurationDao") in your singleton bean does
not fix the problem?
@Singleton
@Startup
@ConcurrencyManagement(ConcurrencyManagementType.BEAN)
@DependsOn("UniversalConfigurationDao")
public class UniversalConfigurationService {
@Inject
UniversalConfigurationDao configDao;
private ConcurrentHashMap<Integer, ConcurrentHashMap<Integer,
ConfigValue>> configCache = new ConcurrentHashMap<>();
@PostConstruct
public void init() {
this.configCache = configDao.getAllConfigurations();
}
}
[]s,
Thiago.
On Tue, Mar 10, 2015 at 4:14 AM, Matej <[email protected]> wrote:
> Hi Romain.
>
> I don't really understand your solution. Can you please provide me with
> simple exmaple.... So I'll understand.
>
> BR
>
> MAtej
>
> 2015-03-09 22:59 GMT+01:00 Romain Manni-Bucau <[email protected]>:
>
> > Why not using a dependson singleton as delegate in your mdb as
> mentionned?
> > Fast and reliable as fix imo
> > Le 9 mars 2015 22:13, "Matej" <[email protected]> a écrit :
> >
> > > Would something like that help. That's probably something what David
> > meant.
> > >
> > > @Singleton
> > > @Startup
> > > @Lock(LockType.READ)
> > > @ConcurrencyManagement(ConcurrencyManagementType.CONTAINER)
> > > public class UniversalConfigurationService {
> > >
> > > @Inject
> > > UniversalConfigurationDao configDao;
> > >
> > > private ConcurrentHashMap<Integer, ConcurrentHashMap<Integer,
> > > ConfigValue>> configCache = new ConcurrentHashMap<>();
> > >
> > > @PostConstruct
> > > @Lock(LockType.WRITE) //probably not nedded right?
> > > public void init() {
> > > this.configCache = configDao.getAllConfigurations();
> > > }
> > > }
> > >
> > > 2015-03-09 19:10 GMT+01:00 Matej <[email protected]>:
> > >
> > > > I added a short stacktrace. Will try to provide better one. Somehow
> is
> > > > seems, like the system is not fully initialized, like some injection
> > > > missing.. Without the (configurationService.getBoolean, everything
> > loads
> > > > normally. Is the MDB system initialized before EJBs?
> > > >
> > > >
> > > > Here is the Singleton snippet:
> > > > @Singleton
> > > > @Startup
> > > > @ConcurrencyManagement(ConcurrencyManagementType.BEAN)
> > > > public class UniversalConfigurationService {
> > > >
> > > > @Inject
> > > > UniversalConfigurationDao configDao;
> > > >
> > > > private ConcurrentHashMap<Integer, ConcurrentHashMap<Integer,
> > > > ConfigValue>> configCache = new ConcurrentHashMap<>();
> > > >
> > > > @PostConstruct
> > > > public void init() {
> > > > this.configCache = configDao.getAllConfigurations();
> > > > }
> > > > }
> > > >
> > > > and here te MDB
> > > >
> > > > MessageDriven(activationConfig = {
> > > > @ActivationConfigProperty(propertyName = "destinationType",
> > > > propertyValue = "javax.jms.Queue"),
> > > > @ActivationConfigProperty(propertyName = "destination",
> > propertyValue
> > > > = "EtaStatisticalRes")})
> > > > @DependsOn("UniversalConfigurationService")
> > > > public class EtaStatisticalResHandler implements MessageListener {
> > > >
> > > > @Inject
> > > > public Logger logger;
> > > >
> > > > @Inject
> > > > UniversalConfigurationService configurationService;
> > > >
> > > > @Override
> > > > public void onMessage(Message message) {
> > > >
> > > > if (configurationService.getBoolean(ETA.getCode(),
> > > > EMBEDDED_ETA_REPORTING.getCode())) {
> > > > return;
> > > > }
> > > > }
> > > >
> > > >
> > > >
> > > >
> > > >
> > > > 2015-03-08 5:31 GMT+01:00 David Blevins <[email protected]>:
> > > >
> > > >> The @DependsOn annotation only works for other @Singleton beans.
> > > >>
> > > >> Definitely use CONTAINER concurrency. Understand that this code is
> > just
> > > >> a plain jvm ReentrantReadWriteLock under the covers. It would be
> hard
> > > to
> > > >> do much better.
> > > >>
> > > >> -
> > > >>
> > >
> >
> http://docs.oracle.com/javase/7/docs/api/java/util/concurrent/locks/ReentrantReadWriteLock.html
> > > >>
> > > >> All methods annotated with an @Lock(READ) acquire a read lock. All
> > > >> methods annotated with @Lock(WRITE) acquire a write lock.
> > > >>
> > > >> That said, if you're already doing the configuration initialization
> in
> > > >> the @PostConstruct of the @Singleton, this issue shouldn't exist.
> > > >>
> > > >> Can you paste the stacktrace of your NPE?
> > > >>
> > > >>
> > > >> --
> > > >> David Blevins
> > > >> http://twitter.com/dblevins
> > > >> http://www.tomitribe.com
> > > >>
> > > >> On Mar 7, 2015, at 3:51 AM, Matej <[email protected]> wrote:
> > > >>
> > > >> > Hi everybody.
> > > >> >
> > > >> > We have an annoying problem on our production system. We have an
> > > >> > Configuration Singleton which reads config things from DB. Then in
> > one
> > > >> MDB
> > > >> > we inject this Singleton to control operation based on configs.
> Our
> > > >> problem
> > > >> > is that the system is quite heavely loadded and while the system
> > > >> startups
> > > >> > already MDB recievs onMessage events while the Singleton still
> > > >> initliazes.
> > > >> > Which produces some NPEs and system doesn't boot.
> > > >> >
> > > >> > The depneds on annotation seems not to help. We are doing BEAN
> > > >> conncurency
> > > >> > management could this be the issue? And the Singleton has an
> > > >> Postconstruct
> > > >> > annotation.
> > > >> >
> > > >> > Anyone has any pattern or tips how to handle this type of
> scenario.
> > > >> >
> > > >> > BR
> > > >> >
> > > >> > Matej
> > > >>
> > > >>
> > > >
> > >
> >
>
