UML class diagram - how to show that one class includes another

Question

I have a situation similar to this:

classA.h:
class A{};

classB.h:
#include "classA.h"
class B{};

Is there a way (and should I do it?) to show that classB uses (includes) classA even though there is no heredity involved? ClassB doesn't even have classA as a member, but I feel like it would make sense to somehow show this in the class diagram.

Answer 1

You can do it two ways. The first is to simply enlarge B so it can hold A like this:

Note the fully qualified name for A.

Another way is to use an import relation: