I downloaded Think in Java 2nd edition(from the address you told someone here). I had the book Think in Java Chinese edition(1st edition). I have read both of them several times before polymorphism. i think most of the phenomenon before polymorphism i had some sense.
I will try to finish all the excercises and examples before polymorphism in two days in the 2nd edition. Maybe it's helpful to understand the concepts.
This post has been archived. It cannot be replied.