Abstract Factory Example (Design Pattern)

abstractFactory.cpp

#include <iostream>

using namespace std;

class Parts {
  string specification;
  
public:
  // Constructor
  Parts(string specification) {
    this->specification = specification;
  }
  
  string getSpecification() {
    return specification;
  }
};

class Computer {
  
public:
  virtual Parts getRAM() = 0;
  virtual Parts getProcessor() = 0;
  virtual Parts getMonitor() = 0;
};

class PC : public Computer {
public:
  Parts getRAM() {
    return Parts("512 MB");
  } 
  
  Parts getProcessor() {
    return Parts("Celeron");
  }
  
  Parts getMonitor() {
    return Parts("15 inches");
  }
};

class Server : public Computer {
public:
  Parts getRAM() {
    return Parts("4 GB");
  } 
  
  Parts getProcessor() {
    return Parts("Inter P4");
  }
  
  Parts getMonitor() {
    return Parts("17 inches");
  }
};


class ComputerType {
  Computer* comp; 

public:
  Computer* getComputer(string computerType) {    
    if (computerType.compare("PC"))
      comp = new PC();
    else if(computerType.compare("Server"))    
      comp = new Server(); 
    
    return comp;
  } 
};

int main() {
  ComputerType type = ComputerType(); 
  Computer* computer = type.getComputer("Server");
  cout << "Monitor: " << computer->getMonitor().getSpecification() << endl;
  cout << "RAM: " << computer->getRAM().getSpecification() << endl;
  cout << "Processor: " << computer->getProcessor().getSpecification() << endl;
  
  return 0;
}