Builder模式和Factory模式的區別是：Builder模式是分步創建對象。在此模型中有個director類，通過它來把切片stream傳遞給builder，通過切片來創建對象。此中模式把部件組合成完整的產品和部件的實現分開，從而實現通過共同的接口的不同實現創建產品。
#include <iostream>
#include <string>
#include <vector>
#include <cstddef>
#include ".../purge.h"
using std::size_t;
class BicyclePart{
public:
enum BPart{FRAME,WHEEL,SEAT,DERAILLEUR,HANDLERBAR,SPROCKET,RACK,SHOCK,NPARTS};
private:
BPart id;
static std::string names[NPARTS];
public:
BicyclePart(BPart bp) {id=bp;}
friend std::ostream& operator<<(std::ostream& os,const BicyclePart& pb){
return os<<bp.names[bp.id];}
};
class Bicycle{
std::vector<BicyclePart*> parts;
public:
~Bicycle() {pruge(parts);}
void addParts(BicyclePart* bp){parts.push_back(bp);}
friend std::ostream& operator<<(std::ostream& os,const Bicycle& b){
os<<"{";
for(size_t i= 0; i < b.parts.size();++i)
os<<*b.parts[i]<<' ';
return os <<"}";}
};
class BicycleBuilder{
protected:
Bicycle* product;
public:
BicycleBuilder(){product = 0;}
void CreateProcuct(){product = new Bicycle;}
virtual void buildFrame()=0;
virtual void buildWheel()=0;
virtual void buildSeat()=0;
virtual void buildDerailleur()=0;
virtual void buildHandlebar()=0;
virtual void buildSprocket()=0;
virtual void buildRack()=0;
virtual void buildShocK()=0;
virtual std::string getBikeName() const =0;
Bicycle* getProduct(){
Bicycle* temp= product;
product = 0; //Relinquish product
return temp;}
};
class MountainBikeBuilder:public BicycleBuilder{
public:
void buildFrame();
void buildWheel();
void buildSeat();
void buildDerailleur();
void buildHandlebar();
void buildSprocket();
void buildRack();
void buildShocK();
std::string getBikeName() const {return "MountainBike"}
};
class TouringBikeBuilder:public BicycleBuilder{
public:
void buildFrame();
void buildWheel();
void buildSeat();
void buildDerailleur();
void buildHandlebar();
void buildSprocket();
void buildRack();
void buildShocK();
std::string getBikeName() const {return "TouringBike"}
};
class RacingBickBuilder:public BicycleBuilder{
public:
void buildFrame();
void buildWheel();
void buildSeat();
void buildDerailleur();
void buildHandlebar();
void buildSprocket();
void buildRack();
void buildShock();
std::string getBickName()const {return "RacingBike";}
};
class BicycleTechnician{
BicycleBuilder* builder;
public:
BicycleTechnician(){builder=0;}
void setBuilder(BicycleBuiler* b) {builder=b;}
void construct();
};
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
std::string BicyclePart::names[NPARTS] ={"Frame","Wheel","Seat","Derailleur","Handlebar","Sprocket","Rack","Shock"};
//MountainBikeBuilder implementation
void MountainBikeBuilder::buildFrame(){product->addpart(new BicyclePart(Bicycle::FRAME));}
void MountainBikeBuilder::buildWheel(){product->addpart(new BicyclePart(Bicycle::WHEEL));}
void MountainBikeBuilder::buildSeat(){product->addpart(new BicyclePart(Bicycle::SEAT));}
void MountainBikeBuilder::buildDerailleur(){product->addpart(new BicyclePart(Bicycle::DERAILLEUR));}
void MountainBikeBuilder::buildHandlebar(){product->addpart(new BicyclePart(Bicycle::HANDLEBAR));}
void MountainBikeBuilder::buildSprocket(){product->addpart(new BicyclePart(Bicycle::SPROCKET));}
void MountainBikeBuilder::buildRack(){}
void MountainBikeBuilder::buildShock(){product->addpart(new BicyclePart(Bicycle::SHOCK));}
//TouringBikeBuilder implementation
void TouringBikeBllider::buildFrame(){product->addpart(new BicyclePart(Bicycle::FRAME));}
void TouringBikeBuilder::buildWheel(){product->addpart(new BicyclePart(Bicycle::WHEEL));}
void TouringBikeBuilder::buildSeat(){product->addpart(new BicyclePart(Bicycle::SEAT));}
void TouringBikeBuilder::buildDerailleur(){product->addpart(new BicyclePart(Bicycle::DERAILLEUR}
void TouringBikeBuilder::buildHandlebar(){product->addpart(new BicyclePart(Bicycle::HANDLEBAR));}
void TouringBikeBuilder::buildSprocket(){product->addpart(new BicyclePart(Bicycle::SPROCKET));}
void TouringBikeBuilder::buildRack(){product->addpart(new BicyclePart(Bicycle::RACK));}
void TouringBikeBuilder::buildShock(){}
//RacingBikeBulider implementation
void RacingBikeBuilder::buildFrame(){product->addpart(new BicyclePart(Bicycle::FRAME));}
void RacingBikeBuilder::buildWheel(){product->addpart(new BicyclePart(Bicycle::WHEEL));}
void RacingBikeBuilder::buildSeat(){product->addpart(new BicyclePart(Bicycle::SEAT));}
void RacingBikeBuilder::buildDerailleur(){}
void RacingBikeBuilder::buildHandlebar(){product->addpart(new BicyclePart(Bicycle::HANDLEBAR));}
void RacingBikeBuilder::buildSprocket(){product->addpart(new BicyclePart(Bicycle::SPROCKET));}
void RacingBikeBuilder::buildRack(){}
void RacingBikeBuilder::buildShock(){}
//BicycleTechnician implementation
void BicycleTechnician::construct(){
assert(builder);
builder->createProduct();
builder->buildFrame();
builder->buildWheel();
builder->buildSeat();
builder->buildDerailleur();
builder->buildHandlbar();
builder->buildSprocket();
builder->buildRack();
builder->buildShock();
};
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
#include <cstddef>
#include <iostream>
#include <map>
#include <vector>
#inculde "../purge.h"
using namespace std;
//constructs a bike via a concrete builder
Bicycle* buildMeBike(BicycleTechnician& t,BicycleBuilder* builder){
t.setBuilder(builder);
t.construct();
Bicycle* b = builder->getProduct();
cout<<"Build a"<<builder->getBikeName()<<endl;
return b;
}
int main(){
//Create an order for some bicycle
map<string,size_t> order;
order["mountain"] = 2;
order["toruing"] = 1;
order["racing"] = 3;
//build bikes
vector<Bicycle*> bikes;
BicycleBuilder* m = new MountainBikeBuilder;
BicycleBuilder* t = new TouringBikeBuilder;
BicycleBuilder* r = new RacingBikeBuilder;
BicycleTechnician tech;
map<string,size_t> ::iterator it = order.begin();
while(it != order.end()){
BicycleBuilder* builder;
if(it->first == "Mountain")
builder = m;
else if(it->first == "touring")
builder = t;
else if(it->first == "racing")
builder = r;
for(size_t i=0; i < it->second; ++i)
bikes.push_back(builderMeABike(tech,builder));
++ it;
}
delete m;
delete t;
delete r;
//Display inventory
for(size_t i = 0; i < bikes.size(); ++i)
cout<<"Bicycle" <<*bikes[i] <<endl;
pruge(bikes);
}