[Ace-users] [ace-users] ACE_Hash_Map_Manager will not link if static

[Douglas C. Schmidt]

Hi David,

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> Here is my problem; I need to have a singleton type object that the whole system sees only one copy of the object. This
> object will manage a key/value pair of queue IDs and queue objects. To do this I have an object that has all static
> attributes and methods. This will ensure that all references to the object will work on the same copy. Since these are key/
> value pairs I want to use some sort of map (or hash table) since the keys have to be unique. The class looks something
> like:
> 
> typedef ACE_Hash_Map_Manager<int, QueueObject *, ACE_Null_Mutex> EventMap;
> 
> class EventDispatcher
> 
> {
> 
>   private:
> 
>     static EventMap m_queueList;
> 
>   public:
> 
>     static bool CreateStaticQueue(int P_queueID);
> 
>     static bool DestroyQueue(int P_queueID);
> 
> };
> 
> If I declare the EventMap and the methods without the static keyword the code links. Once I declare the EventMap and the
> methods static I get an unresolved symbol error in the linker:
> 
> error LNK2001: unresolved external symbol "private: static class ACE_Hash_Map_Manager<int,class QueueObject *,class
> ACE_Null_Mutex> EventDispatcher::m_queueList" (?m_queueList at EventDispatcher@@0V?
> $ACE_Hash_Map_Manager at HPAVQueueObject@@VACE_Null_Mutex@@@@A)
> 
> What do I have to do to get the ACE_Hash_Map_Manager to link as a static?

I think this is a C++ question, not an ACE question.  Please see

http://publib.boulder.ibm.com/infocenter/lnxpcomp/v8v101/index.jsp?topic=/com.ibm.xlcpp8l.doc/language/ref/cplr038.htm

for how to do this.

Thanks,

        Doug