/*
 * C++ Design Patterns: Proxy
 * Author: Jakub Vojvoda [github.com/JakubVojvoda]
 * 2016
 *
 * Source code is licensed under MIT License
 * (for more details see LICENSE)
 *
 */

#include <iostream>

/*
 * Subject
 * defines the common interface for RealSubject and Proxy
 * so that a Proxy can be used anywhere a RealSubject is expected
 */
class Subject
{
public:
 virtual ~Subject() { /* ... */ }

 virtual void request() = 0;
 // ...
};

/*
 * Real Subject
 * defines the real object that the proxy represents
 */
class RealSubject : public Subject
{
public:
 void request()
 {
 std::cout << "Real Subject request" << std::endl;
 }
 // ...
};

/*
 * Proxy
 * maintains a reference that lets the proxy access the real subject
 */
class Proxy : public Subject
{
public:
 Proxy()
 {
 subject = new RealSubject();
 }
 
 ~Proxy()
 {
 delete subject;
 }
 
 void request()
 {
 subject->request();
 }
 // ...

private:
 RealSubject *subject;
};


int main()
{
 Proxy *proxy = new Proxy();
 proxy->request();
 
 delete proxy;
 return 0;
}