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copied!<p>I referred to this article to implement a self-registering class factory similar to the one described in TimW's answer, but it has the nice trick of using a templated factory proxy class to handle the object registration. Well worth a look :)</p> <p>Self-Registering Objects in C++ -> <a href="http://www.ddj.com/184410633" rel="nofollow noreferrer">http://www.ddj.com/184410633</a></p> <p><strong>Edit</strong></p> <p>Here's the test app I did (tidied up a little ;):</p> <p>object_factory.h</p> <pre><code>#include <string> #include <vector> // Forward declare the base object class class Object; // Interface that the factory uses to communicate with the object proxies class IObjectProxy { public: virtual Object* CreateObject() = 0; virtual std::string GetObjectInfo() = 0; }; // Object factory, retrieves object info from the global proxy objects class ObjectFactory { public: static ObjectFactory& Instance() { static ObjectFactory instance; return instance; } // proxies add themselves to the factory here void AddObject(IObjectProxy* object) { objects_.push_back(object); } size_t NumberOfObjects() { return objects_.size(); } Object* CreateObject(size_t index) { return objects_[index]->CreateObject(); } std::string GetObjectInfo(size_t index) { return objects_[index]->GetObjectInfo(); } private: std::vector<IObjectProxy*> objects_; }; // This is the factory proxy template class template<typename T> class ObjectProxy : public IObjectProxy { public: ObjectProxy() { ObjectFactory::Instance().AddObject(this); } Object* CreateObject() { return new T; } virtual std::string GetObjectInfo() { return T::TalkToMe(); }; }; </code></pre> <p>objects.h</p> <pre><code>#include <iostream> #include "object_factory.h" // Base object class class Object { public: virtual ~Object() {} }; class ClassA : public Object { public: ClassA() { std::cout << "ClassA Constructor" << std::endl; } ~ClassA() { std::cout << "ClassA Destructor" << std::endl; } static std::string TalkToMe() { return "This is ClassA"; } }; class ClassB : public Object { public: ClassB() { std::cout << "ClassB Constructor" << std::endl; } ~ClassB() { std::cout << "ClassB Destructor" << std::endl; } static std::string TalkToMe() { return "This is ClassB"; } }; </code></pre> <p>objects.cpp</p> <pre><code>#include "objects.h" // Objects get registered here ObjectProxy<ClassA> gClassAProxy; ObjectProxy<ClassB> gClassBProxy; </code></pre> <p>main.cpp</p> <pre><code>#include "objects.h" int main (int argc, char * const argv[]) { ObjectFactory& factory = ObjectFactory::Instance(); for (int i = 0; i < factory.NumberOfObjects(); ++i) { std::cout << factory.GetObjectInfo(i) << std::endl; Object* object = factory.CreateObject(i); delete object; } return 0; } </code></pre> <p>output:</p> <pre><code>This is ClassA ClassA Constructor ClassA Destructor This is ClassB ClassB Constructor ClassB Destructor </code></pre>

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