builder pattern.cpp

#include <iostream>

using namespace std;



// Your end product 

class Plane{

    string _plane;

    string _body;

    string _engine;

public:

    Plane(string planeType):_plane{planeType} {}

    void setEngine(string type) { _engine = type; }

    void setBody(string body)   { _body = body;   }

    string getEngine()          { return _engine; }

    string getBody()            { return _body;   }

    

    void show() {

    	cout << "Plane Type: " <<_plane << endl

    		 << "Body Type: " <<_body << endl

    		 << "Engine Type: "<<_engine << endl << endl;

    }

};



// PlaneBuilder Abstract Class

// Means all builders should have atleast these methods

class PlaneBuilder{

protected:

    Plane *_plane;

public:

    virtual void getPartsDone() = 0;

    virtual void buildBody() = 0;

    virtual void buildEngine() = 0;

    //virtual ~PlaneBuilder(){}

    Plane* getPlane(){ return _plane; }

};



// PlaneBuilder concrete class

// knows only how to build Propeller Plane

class PropellerBuilder: public PlaneBuilder {

public:

    void getPartsDone() { _plane = new Plane("Propeller Plane"); }

    void buildEngine()  { _plane->setEngine("Propeller Engine");   }

    void buildBody()    { _plane->setBody("Propeller Body");   }

    //~PropellerBuilder(){delete _plane;}

};



// PlaneBuilder concrete class

// Knows only how to build Jet Plane

class JetBuilder: public PlaneBuilder {

public:

    void getPartsDone() { _plane = new Plane("Jet Plane"); }

    void buildEngine()  { _plane->setEngine("Jet Engine");   }

    void buildBody()    { _plane->setBody("Jet Body");   }

    //~JetBuilder(){delete _plane;}

};



// Defines steps and tells to the builder that build in given order.

class Director{

    PlaneBuilder *builder;

public:

    Plane* createPlane(PlaneBuilder *builder) {

        builder->getPartsDone();

        builder->buildBody();

        builder->buildEngine();

        return builder->getPlane();

    }

};



int main() {

	

    Director dir;

    JetBuilder jb;

    PropellerBuilder pb;



	Plane *jet = dir.createPlane(&jb);

	Plane *pro = dir.createPlane(&pb);

	

	jet->show();

	pro->show();

    

    delete jet;

    delete pro;



	return 0;

}