How do I make the method return type generic?

Question

Consider this example (typical in OOP books):

I have an Animal class, where each Animal can have many friends.
And subclasses like

Answer 1

what about

public class Animal {
private Map> friends = new HashMap>();

public  void addFriend(String name, T animal){
    friends.put(name,animal);
}

public  T callFriend(String name){
    return friends.get(name);
}

}