This is just my opinion, but I suspect that this is a "feature" of
Guice, and I don't know of a way to configure different behavior, but
maybe one exists.
I know in your case its the same exception causing the 3 bindings to
fail, but if there were 3 different exceptions while resolving
bindings, Guice will catch the first one and continue on, printing out
the total list of exceptions that occurred while configuring your
module. This can be useful when wiring up your application for the
first time, if it failed fast you'd find the first problem, fix it,
deploy, find the next problem, etc.
For your case, you might be able to separate your bindings using a
child injector to get the behavior you want. Something like:
Injector injector = Guice.createInjector(new AbstractModule() {
@Override
protected void configure() {
bind(Service.class).to(FaultyService.class).asEagerSingleton();
}
});
Injector childInjector = injector.createChildInjector(new
AbstractModule() {
@Override
protected void configure() {
bind(ClassA.class).asEagerSingleton();
bind(ClassB.class).asEagerSingleton();
}
});
This way if FaultyService throws an exception, the application won't
even try to create the child injector.
On Jul 26, 5:13 am, Lóránt Pintér <[email protected]> wrote:
> Hi,
>
> I have a system configured via Guice 3.0, built up of many services.
> Many of these services are configured as eager singletons. Each
> service can fail to start up, and throw an exception in its
> constructor. The behavior I'd like to get is if any of the services
> throws an exception, the whole Guice.createInjector() call should stop
> at that point throwing that exception. However, I don't seem to manage
> to get this from Guice.
>
> Currently if a low-level service (such as my JdbcConnectionService
> that is the basis of all database-based services) fails to start up,
> Guice seems to continue to try to instantiate other eager singletons,
> and when those ask for the failed low-level service, Guice tries to
> instantiate it again.
>
> In the end there are two problems with this:
> * I get dozens of exceptions that are hard to decipher. A single
> exception with the original problem would be a lot easier to handle.
> It's not important for me if it gets wrapped in CreationException/
> ProvisionException or not.
> * Some of my low-level services have side-effects, like static
> registries being initialized. (Yeah, I know, but this is a legacy
> project I'm trying to convert.) If their constructor gets called
> multiple times, all kinds of problems can arise.
>
> So, to sum it up, all I want is Guice.createInjector() to fail fast
> when it encounters a problem creating eager singletons. How can I get
> there? I'm not using ThrowingProviders, and it doesn't strike me as
> the tool I'd need for the job either. I'd like to inject object
> instances, and not juggle around with Providers if I don't have to.
>
> Thanks,
> Lorant
>
> PS: Here's a little sample code to demonstrate what I would like to
> have. Currently I get 3 errors, and my FaultyService() constructor
> gets called three times. What I would like to have is to stop at the
> first exception thrown by FaultyService():
>
> import com.google.inject.AbstractModule;
> import com.google.inject.Guice;
> import com.google.inject.Inject;
> import com.google.inject.Scopes;
>
> public class GuiceExceptionsTest {
>
> public static void main(String[] args) {
> Guice.createInjector(new AbstractModule() {
> @Override
> protected void configure() {
>
> bind(Service.class).to(FaultyService.class).asEagerSingleton();
> bind(ClassA.class).asEagerSingleton();
> bind(ClassB.class).asEagerSingleton();
> }
> });
> // Throws 3 exceptions, one for each class
> }
>
> interface Service {}
>
> static class ClassA {
> @Inject
> ClassA(Service service) {}
> }
>
> static class ClassB {
> @Inject
> ClassB(Service service) {}
> }
>
> static class FaultyService implements Service {
> static int counter = 0;
> FaultyService() {
> throw new RuntimeException("Error #" + ++counter);
> }
> }
>
>
>
>
>
>
>
> }
--
You received this message because you are subscribed to the Google Groups
"google-guice" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/google-guice?hl=en.
