Refactor dependecy injection of 32 classes that extend the same abstract class with Dagger

Question

I'm working on a project with Vert.x that uses Dagger for DI, and there's a class that's creating an unsustainable problem with how big the injection is done.

This is the class that I have:

public class ClassManager {
    private List<ParentClass> all = new ArrayList<>();

    @Inject
    public ClassManager(ParentClass... classes) {
        if (classes != null) {
            all.addAll(Arrays.asList(classes));
        }
    }
    //other methods down here
}

The problem being that, as of right now, we have 32 classes that extend from this abstract class ParentClass, so the injection right now is as this:

    @Provides
    @Singleton
    public ClassManager provideClassManager(SubClassA a, SubClassB b, SubClassC c.... and so on) {
         return new ClassManager(a, b, c...and so on);
    }

I haven't found so far a better solution on how to do this injection with Dagger, but I do need that this ClassManager has access to all of the classes that extend from ParentClass. Is there any other better way? Maybe with other library?

Have you tried using the dagger verticle factory approach? It's described [here](https://medium.com/@michel.werren/dependency-injection-in-vert-x-with-dagger-2-7087bc6b9f4f) — Selim, Nov 25 '21 at 14:11
or just something like [this](https://stackoverflow.com/q/205573/592355)/[that](https://stackoverflow.com/q/347248/592355)? — xerx593, Nov 29 '21 at 15:14

score 0 · Answer 1 · answered Feb 02 '22 at 20:22

You can use dagger multibindings and bind your subclasses into set, like this

@Module
public abstract class SubClassModule {

    @Binds
    @IntoSet
    public abstract ParentClass bindsSubClassA(impl: SubClassA);

    @Binds
    @IntoSet
    public abstract ParentClass bindsSubClassB(impl: SubClassB)
}

And in module with class manager pass set into constructor

@Provides
@Singleton
public ClassManager provideClassManager(Set<ParentClass> set) {
    return new ClassManager(set);
}

Refactor dependecy injection of 32 classes that extend the same abstract class with Dagger

This is the class that I have:

1 Answers1