Question

Consider a certain class hierarchy consisting of a root class and some subclasses

    R
    |
 .--+--+------.
 |     |  ... |
S1     S2 ... Sn

Class R has a field x of a certain type, say X, which is not a simple type, that every subclass should inherit. Subclasses can do sorts of internal processing on field x as well as expose it as a property.
Sort of a discussion arose about which of these two coding style was preferrable:

1st solution

Have class R declare x as a private field and provide public getter and setter

class R {
    ....
    private X x;

    ....

    public X getX() { ... }
    public void setX(X ax) { ... }
}

2nd solution

Have class R declare x as a protected field

Which one, in your opinion, could be the preferrable solution?

Answer 1

It depends what you want to allow to be done to the inner X. If you want it to be accessible/modifiable from outside make public get/set. But if you want them to be only modifiable by its subclasses then use protected and that is all. IMHO