Java Generics: Implement multiple sub-interfaces of an generic interface

I've following codes.

interface Observer<T> {
    void update();
}

interface FirstClassObserver extends Observer<FirstClass>{ }

interface SecondClassObserver extends Observer<SecondSecond> { }

Now, I'm required to do as follows.

class MainClass implements FirstClassObserver, SecondClassObserver {
}

But Eclipse give following problem with the code.

The interface Observer cannot be implemented more than once with different arguments: FirstClassObserver<FirstClass> and SecondClassObserver<SecondClass>

Is there a way that I can write my MainClass like

class MainClass implements FirstClassObserver, SecondClassObserver {
   @Override
   void FirstClassObserver::update() { /* ... / }
   @Override
   void SecondClassObserver::update() { / ... */ }
}