Summary of Heuristics
Heuristic 2.1 All data should be
hidden within its class.
Heuristic 2.2 Users of a class
must be dependent on its public interface, but a class should not be dependent
on its users.
Heuristic 2.3 Minimize the
number of messages in the protocol of a class.
Heuristic 2.4 Implement a
minimal public interface that all classes understand [e.g., operations such as
copy (deep versus shallow), equality testing, pretty printing, parsing from an
ASCII description, etc.].
Heuristic 2.5 Do not put
implementation details such as common-code private functions into the public
interface of a class.
Heuristic 2.6 Do not clutter the
public interface of a class with things that users of that class are not able to
use or are not interested in using.
Heuristic 2.7 Classes should
only exhibit nil or export coupling with other classes, that is, a class should
only use operations in the public interface of another class or have nothing to
do with that class.
Heuristic 2.8 A class should
capture one and only one key abstraction.
Heuristic 2.9 Keep related data
and behavior in one place.
Heuristic 2.10 Spin off
nonrelated information into another class (i.e., noncommunicating behavior).
Heuristic 2.11 Be sure the
abstractions that you model are classes and not simply the roles objects
play.
既然没有什么好说的，就不要说了，还不如静下心来搞些设计，在实践中体会OOD的精髓...... Practice make perfect!