Composition, I don't quite get this?

Question

Referring to the below link:

http://www.javaworld.com/javaworld/jw-11-1998/jw-11-techniques.html?page=2

The composition approach to code reuse pro

Answer 1

Return type of Fruit.peel() is being changed from int to Peel. This doesn't meant that the return type of Apple.peel() is being forced to change to Peel as well. In case of inheritance, it is forced and any client using Apple has to be changed. In case of composition, Apple.peel() still returns an integer, by calling the Peel.getPeelCount() getter and hence the client need not be changed and hence Apple's interface is not changed ( or being forced to be changed)