I'm trying to extend MutableLiveData in multiple classes, each one extends the previous, like (those following rows could be copy/pasted directly in java file to test/lint them):

class ALiveData<T> extends MutableLiveData<T> { }
interface OneInterface {
    void methodOne();
}
class BLiveData<K,T> extends ALiveData<OneInterface> {
    @Override
    public void observe(LifecycleOwner owner, Observer<? super OneInterface> observer) {
        // THIS IS OK
    }
}
interface TwoInterface<K,T> extends OneInterface {
    void mathodTwo();
}
abstract class SomeClass<K,T> implements TwoInterface<K,T> { }
class CLiveData<K,T> extends BLiveData<K,List<T>> {
    @Override
    public void observe(LifecycleOwner owner, Observer<? super TwoInterface<K,T>> observer) {
        // not valid in compilation
    }
    @Override
    public void observe(LifecycleOwner owner, Observer<SomeClass<K,T>> observer) {
        // not valid in compilation
    }
    @Override
    public void observe(LifecycleOwner owner, Observer<? super OneInterface> observer) {
        // this is the only accepted observer() but I don't want to
        // observe by its basic OneInterface because it doesn't have
        // all TwoInterface methods and I don't want the caller need
        // to cast it every time.
    }
}
//------- testing instantiations --------
{
    (new CLiveData<Byte,Integer>()).observe(null, new Observer<TwoInterface<Byte, Integer>>() {
        @Override
        public void onChanged(TwoInterface<Byte, Integer> byteIntegerTwoInterface) {
            
        }
    });
}

I would like to be able to CLiveData.observe() by passing a new Observer<TwoInterface<Byte,Integer>> and not the basic new Observer<? super OneInterface>, because who will observe CLiveData needs to use TwoInterface and not its basic OneInterface.

What am I missing?

class BLiveData<K,T,D extends OneInterface> extends ALiveData<D> {
    @Override
    public void observe(LifecycleOwner owner, Observer<? super D> observer) {
        // ...
    }
}

class CLiveData<K,T> extends BLiveData<K,List<T>,TwoInterface<K,T>> {
    @Override
    public void observe(LifecycleOwner owner, Observer<? super TwoInterface<K,T>> observer) {
        // ...
    }
}