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@mbains
Created August 20, 2012 17:59
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Factory pattern using C++ templates
#include <iostream>
#include <map>
using namespace std;
class BaseClass{
public:
virtual int funk() {
return 0;
}
};
class DerivedClassA : public BaseClass
{
private:
static short ID;
virtual int funk() {
return 42;
}
public:
DerivedClassA(){};
virtual ~DerivedClassA(){};
};
class DerivedClassB : public BaseClass
{
private:
static short ID;
virtual int funk() {
return 63;
}
public:
DerivedClassB(){};
virtual ~DerivedClassB(){};
};
template<typename Type> BaseClass* createType() {
cout << "creating type \n";
return new Type;
}
class TemplatedFactory
{
public:
typedef BaseClass* (*ComponentFactoryFuncPtr)();
typedef map<const char*, ComponentFactoryFuncPtr> map_type;
map_type m_Map;
public:
template<typename Type>
short AddType(const char* componentName){
ComponentFactoryFuncPtr function = &createType<Type>;
m_Map.insert(std::make_pair(componentName, function));
return 0;
};
};
int main(int argc, char ** argv)
{
TemplatedFactory * factory_p = new TemplatedFactory();
factory_p->AddType<DerivedClassA>("DerivedClassA");
factory_p->AddType<DerivedClassB>("DerivedClassB");
cout << "Done registering\n";
TemplatedFactory::map_type::iterator iterA = factory_p->m_Map.find("DerivedClassA");
TemplatedFactory::map_type::iterator iterB = factory_p->m_Map.find("DerivedClassB");
cout << "DerivedClassA: " << iterA->second()->funk() << "\n";
cout << "DerivedClassB: " << iterB->second()->funk() << "\n";
return 0;
}
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