Builder 模式

Builder 模式和 AbstractFactory 模式在功能上很相似，因为都是用来创建大的复杂的对象，它们的区别是：Builder 模式强调的是一步步创建对象，并通过相同的创建过程可以获得不同的结果对象，一般来说 Builder 模式中对象不是直接返回的。而在 AbstractFactory 模式中对象是直接返回的，AbstractFactory模式强调的是为创建多个相互依赖的对象提供一个同一的接口。

////////////Product.h//////////////////////
#ifndef _PRODUCT_H_
#define _PRODUCT_H_    
#include <vector>
#include <string>
class Product
{
public:

    Product();
    ~Product();
    void Add( std::string part);
    void Show();

protected:
private:
    std::vector<std::string> svec;
};

#endif

////////////Product.cpp//////////////////////
#include "Product.h"
#include <iostream>
using namespace std;

void Product::Add( string part)
{
    svec.push_back(part);
}

void Product::Show()
{
    vector<string>::iterator it = svec.begin();
    while (it != svec.end())
    {
        cout<<*it<<" ";
        it++;
    }
    cout<<endl;
}

Product::Product(){}
Product::~Product(){}

////////////Builder.h//////////////////////
#ifndef _BUILDER_H
#define _BUILDER_H    
#include <string>
using namespace std;

class Product ;
class Builder
{
public:
    virtual ~Builder();
    virtual void BuildPartA() = 0 ;
    virtual void BuildPartB() = 0 ;
    virtual void BuildPartC() = 0 ;
    virtual Product* GetProduct() = 0 ;
protected:
    Builder();
private:

};

class ConcreteBuilder : public Builder
{
public:
    ~ConcreteBuilder();
     ConcreteBuilder();

     void BuildPartA();
     void BuildPartB();
     void BuildPartC();
     Product* GetProduct();
protected:
private:
    Product* product;
};


class ConcreteBuilder2 : public Builder
{
public:
    ~ConcreteBuilder2();
    ConcreteBuilder2();

    void BuildPartA();
    void BuildPartB();
    void BuildPartC();
    Product* GetProduct();
protected:
private:
    Product* product;
};


#endif

/////////Builder.cpp//////////////////
#include "Builder.h"
#include "Product.h"
#include <iostream>
using namespace std;

Builder::Builder(){}
Builder::~Builder(){}

ConcreteBuilder::ConcreteBuilder()
{
    product = NULL;
}
ConcreteBuilder::~ConcreteBuilder()
{

}
void ConcreteBuilder::BuildPartA()
{
    product = new Product();
    product->Add("A");
    cout<<"加入A"<<endl;
}

void ConcreteBuilder::BuildPartB()
{
    product->Add("B");
    cout<<"加入B"<<endl;
}

void ConcreteBuilder::BuildPartC()
{
    product->Add("C");
    cout<<"加入C"<<endl;
}

Product* ConcreteBuilder::GetProduct()
{
    return product ;
}



ConcreteBuilder2::ConcreteBuilder2()
{
    product = NULL;
}
ConcreteBuilder2::~ConcreteBuilder2()
{

}
void ConcreteBuilder2::BuildPartA()
{
    product = new Product();
    product->Add("x");
    cout<<"加入x"<<endl;
}

void ConcreteBuilder2::BuildPartB()
{
    product->Add("y");
    cout<<"加入y"<<endl;
}

void ConcreteBuilder2::BuildPartC()
{
    product->Add("z");
    cout<<"加入z"<<endl;
}

Product* ConcreteBuilder2::GetProduct()
{
    return product ;
}

////////////////////////////Director.h//////////////////////////////////////////////
#ifndef _DIRECTOR_H
#define _DIRECTOR_H

class Builder;
class Director
{
public:
    Director( Builder* bld);

    ~Director();

    void  Construct();
protected:
private:
    Builder* _bld ;
};

#endif

//////////////////////////////Director.cpp////////////////////////////////////////////
#include "Director.h"
#include "Builder.h"
using namespace std ;

Director::Director(Builder* bld)
{
    _bld = bld ;
}
Director::~Director()
{
}
void Director::Construct()
{
    _bld->BuildPartA();
    _bld->BuildPartB();
    _bld->BuildPartC();
}

/////////////////////////////main.cpp/////////////////////////////////////////////
#include "Builder.h"
#include "Director.h"
#include "Product.h"
using namespace std;

int main()
{
    Builder* b1 = new ConcreteBuilder();
    Director* d1 = new Director(b1);
    d1->Construct();
    Product* p1 = b1->GetProduct();
    p1->Show();

    Builder* b2 = new ConcreteBuilder2();
    Director* d2 = new Director(b2);
    d2->Construct();
    Product* p2 = b2->GetProduct();
    p2->Show();

    system("pause");
    return 0;
}

以上代码都是经过测试可以正常运行的哦···········