Object oriented design suggestion

Question

Here is my code:

class Soldier {
public:
   Soldier(const string &name, const Gun &gun);
   string getName();
private:
   Gun gun;
   string name;
};

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Answer 1

Usually my decision is based on the nature of the container class (in this case, Soldier). Either it is entirely a POD or is not. If it's not a POD, I make all data members private and provide accessor methods. The class is a POD only if it has no invariants (i.e. there is no way an external actor can make its state inconsistent by modifying its members). Your soldier class looks more like a non-POD to me, so I would go to the accessor method option. If it would return a const reference or a regular reference is your own decision, based on the behaviour of fire() and the other methods (if they modify gun's state or not).

BTW, Bjarne Stroustrup talks a little about this issue in his site: http://www.artima.com/intv/goldilocks3.html

A sidenote: I know that's not precisely what you asked, but I'd advice you to also consider the many mentions made in other answers to the law of Demeter: to expose action methods (that act on gun) instead of the entire gun object via a getter method. Since the soldier "has" the gun (it is in his hand and he pulls the trigger), it seems more natural to me that the other actors "ask" the soldier to fire. I know this may be tedious if gun has many methods to act on, but maybe also these could be grouped in more high-level actions that the soldier exposes.