How to inject Injector?

Question

Situation: i need lazy dependency instantiation in some FooClass, so i pass Injector to class as a constructor parameter.

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Answer 1

The arguments that you probably shouldn't be injecting an instance of Injector are quite valid, but as with any rule there are exceptions.

I have a factory class that takes in class references for which it needs to provide an instance. The instances aren't necessarily known (really, they are, but there are a lot and there might be more) so I can't make Providers for all of them.

public class ThingFactory {
    private Injector injector;

    @Inject
    ThingFactory(Injector injector) {
        this.injector = injector;
    }

    public  T getInstance(Class aClass) {
        return injector.getInstance(aClass);
    }
}

The real class in my app is extending and overriding another class—that's why this class is basically a passthrough to Guice.