Should I use static data members? (C++)

Question

Let's consider a C++ class. At the beginning of the execution I want to read a set of values from an XML file and assign them to 7 of the data members of this class. Those values do not change during the whole execution and they have to be shared by all the objects / instances of the class in question. Are static data members the most elegant way to achieve this behavior? (Of course, I do not consider global variables)

Answer 1

As others have mentioned, the use of static members in this case seems appropriate. Just remember that it is not foolproof; some of the issues with global data apply to static members:

• You cannot control the order of initialization of your static members, so you need to make sure that no globals or other statics refer to these objects. See this C++ FAQ Question for more details and also for some tips for avoiding this problem.
• If your accessing these in a multi-threaded environment you need to make sure that the members are fully initialized before you spawn any threads.

Answer 2

Sounds like a good use of static variables to me. You're using these more as fixed parameters than variables, and the values legitimately need to be shared.

Answer 3

static members would work here and are perfectly acceptable. Another option is to use a singleton pattern for the class that holds these members to ensure that they are constructed/set only once.