Added factory method example source code.

examples/creational/factory_method.cpp

@@ -0,0 +1,69 @@
+#include <iostream>
+#include <memory>
+
+class Interviewer
+{
+  public:
+    typedef std::shared_ptr<Interviewer> ptr_t;
+    virtual void askQuestions(void) = 0;
+};
+
+class Developer : public Interviewer
+{
+  public:
+    void askQuestions(void)
+    {
+      std::cout << "Asking about design patterns!" << std::endl;
+    }
+};
+
+class CommunityExecutive : public Interviewer
+{
+  public:
+    void askQuestions(void)
+    {
+      std::cout << "Asking about community building!" << std::endl;
+    }
+};
+
+class HiringManager
+{
+  public:
+    void takeInterview(void)
+    {
+      Interviewer::ptr_t interviewer = makeInterviewer();
+      interviewer->askQuestions();
+    }
+
+  protected:
+    virtual Interviewer::ptr_t makeInterviewer(void) = 0;
+};
+
+class DevelopmentManager : public HiringManager
+{
+  protected:
+    Interviewer::ptr_t makeInterviewer(void)
+    {
+      return std::make_shared<Developer>();
+    }
+};
+
+class MarketingManager : public HiringManager
+{
+  protected:
+    Interviewer::ptr_t makeInterviewer(void)
+    {
+      return std::make_shared<CommunityExecutive>();
+    }
+};
+
+int main()
+{
+  DevelopmentManager developmentManager = DevelopmentManager();
+  developmentManager.takeInterview(); // Output: Asking about design patterns!
+
+  MarketingManager marketingManager = MarketingManager();
+  marketingManager.takeInterview(); // Output: Asking about community building!
+
+  return 0;
+}