/////////////////////////////////////////////////////////////////////////
//  policy.cpp - demonstrate programming to interfaces, policy level   //
//                                                                     //
//  Jim Fawcett, CSE687 - Object Oriented Design, Spring 2002          //
/////////////////////////////////////////////////////////////////////////

#include <iostream>
#include "creatable.h"        // include object factory
#include "implemInterface.h"  // include implementation interface

/////////////////////////////////////////////////////////////////////
// Note that policy does not include any implementation layer headers.
// It includes just the factory and interface headers, which contain
// no implementation details.
//
void main() {

  std::cout << "\n  Demonstate Programming to Interfaces "
            << "\n ======================================\n";

  //////////////////////////////////////////////////////////////////
  // Create an implementation factory and use its interface to
  // register its objects with the factory.

  objFactory<tester> testerFactory;
  tester::registerObjects(testerFactory);

  /////////////////////////////////////////////////////////////////
  // Policy needs to know how to access the ids of the implementation
  // classes it uses, but does not need to bind to the class names.

  tester *pTester1 = testerFactory.makeObj(tester::type(1));
  pTester1->announcer();  // polymorphic call
  delete pTester1;

  tester *pTester2 = testerFactory.makeObj(tester::type(2));
  pTester2->announcer();  // polymorphic call
  delete pTester2;

  std::cout << std::endl;
  std::cout << "\n  The testerFactory delivers, via tester pointers,"
            << "\n  objects that derive from tester.  The tester interface"
            << "\n  provides a protocol for clients of all derived class"
            << "\n  objects, like test1 and test2, to use, without needing"
            << "\n  to know the derived class of the object they are using.";
  std::cout << "\n\n";
}