[Oracle interview]What are some alternatives to inheritance?

Delegation  is an alternative to inheritance. Delegation means that you include an  instance of another class as an instance variable, and forward messages to  the instance. It is often safer than inheritance because it forces you to  think about each message you forward, because the instance is of a known  class, rather than a new class, and because it doesn't force you to accept  all the methods of the super class: you can provide only the methods that  really make sense. On the other hand, it makes you write more code, and it is  harder to re-use (because it is not a subclass).