问题
I have a Jersey resource with a facade object injected. This is configured in my ResourceConfig
and the facade gets injected fine. The facade contains a DAO class which also should be injected and is configured in the same ResourceConfig
. Now to my problem; the DAO class is null. Thus, not injected.
@ApplicationPath("/service")
public class SystemSetup extends ResourceConfig {
public SystemSetup() {
packages(false, "com.foo.bar");
packages("org.glassfish.jersey.jackson");
register(JacksonFeature.class);
final LockManager manager = getLockManager();
final SessionFactory sessionFactory = getSessionFactory();
register(new AbstractBinder() {
@Override
protected void configure() {
bindFactory(InjectFactory.getDaoFactory(sessionFactory)).to(Dao.class).in(Singleton.class);
bindFactory(InjectFactory.getFacadeFactory(manager)).to(Facade.class).in(Singleton.class);
}
});
}
@Path("/")
@Produces("text/json")
public class ViewResource {
@Inject
private Facade logic;
public class Facade {
@Inject
private Dao dao; //Not injected
The factory instances are rather simple. They simply call the constructor and pass the argument to it.
The strange thing is that this worked absolut fine when I used bind(Class object) rather than bindFactory.
EDIT
Factories
class InjectFactory {
static Factory<Dao> getDaoFactory() {
return new Factory<Dao>() {
@Override
public Dao provide() {
return new Dao(new Object());
}
@Override
public void dispose(Dao dao) {}
};
}
static Factory<Facade> getFacadeFactory() {
return new Factory<Facade>() {
@Override
public Facade provide() {
return new Facade();
}
@Override
public void dispose(Facade facade) {}
};
}
}
回答1:
As is the case with most Di frameworks, when you start instantiating things yourself, it's often the case that you are kicking the framework out of the equation. This holds true for the Factory
instances, as well as the objects the factory creates. So the Facade
instance never gets touch by the framework, except to inject it into the resource class.
You can can a hold of the ServiceLocator
, and explicitly inject objects yourself if you want to create them yourself. Here are a couple options.
1) Inject the ServiceLocator
into the Factory
instance, then inject the Facade
instance.
static Factory<Facade> getFacadeFactory() {
return new Factory<Facade>() {
@Context
ServiceLocator locator;
@Override
public Facade provide() {
Facade facade = new Facade();
locator.inject(facade);
return facade;
}
@Override
public void dispose(Facade facade) {}
};
}
@Inject
public SystemSetup(ServiceLocator locator) {
packages("foo.bar.rest");
packages("org.glassfish.jersey.jackson");
register(JacksonFeature.class);
register(new AbstractBinder() {
@Override
protected void configure() {
bindFactory(InjectFactory.getDaoFactory()).to(Dao.class);
Factory<Facade> factory = InjectFactory.getFacadeFactory();
locator.inject(factory);
bindFactory(factory).to(Facade.class);
}
});
}
2) Or bind a Factory
class, and let the framework inject the ServiceLocator
public static class FacadeFactory implements Factory<Facade> {
@Context
ServiceLocator locator;
@Override
public Facade provide() {
Facade facade = new Facade();
locator.inject(facade);
return facade;
}
@Override
public void dispose(Facade facade) {}
}
register(new AbstractBinder() {
@Override
protected void configure() {
bindFactory(InjectFactory.getDaoFactory()).to(Dao.class);
bindFactory(InjectFactory.FacadeFactory.class).to(Facade.class);
}
});
来源:https://stackoverflow.com/questions/34599145/inject-not-working-for-nested-objectsjersey-2-22-1