dependency injection - How to inject Injector?

Question

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

private final Injector m_injector;

public FooClass(@Named("FooInjector") Injector injector) {
m_injector = injector;
}

But guice doesn't permit to bind core classes (injectors, modules and etc). What is the solution?

Answer 1

You should not be using the Injector directly. Rather pass in the Provider<FooClass> instead. Also, you should be injecting the provider in the places where you use FooClass.

private final Provider<FooClass> provider;

@Inject
public ClassWhereFooIsUsed(Provider<FooClass> provider) {
    this.provider = provider;
}

.... somewhere else
FooClass f = provider.get(); // This is lazy