009 --- 第13章 建造者模式

简述：

　　建造者模式将一个复杂的对象构建与它的表示分离，使得同样的构建过程可以创建不同的表示。

　　建造者模式包括：指挥者类、抽象建造者类、具体建造者类、具体产品类。

　　　　指挥者类：构建一个使用抽象建造者接口的对象。

　　　　抽象建造者类：为创建一个具体产品类对象的各个部件指定的抽象接口。

　　　　具体建造者类：实现抽象建造者类接口，构造和装配各个部件。

　　　　具体产品类：具体产品。

建造者模式代码：

#include <iostream>
#include <list>
#include <string>
using namespace std;


// 建造者模式
// 具体产品类
class CProduct
{
private:
    list<string> m_listParts;

public:
    void Add(string szPart)
    {
        m_listParts.push_back(szPart);
    }

    void Show()
    {
        cout << "产品创建-----" << endl;
        for (auto szPart : m_listParts)
            cout << szPart << endl;
    }
};

// 抽象建造者类
class CBuilder
{
public:
    virtual void BuildPartA() {};
    virtual void BuildPartB() {};
    CProduct* GetResult() {};
};

// 具体建造者类
class CConcreteBuilder1 : public CBuilder
{
private:
    CProduct* m_pProduct;

public:
    CConcreteBuilder1()
    {
        m_pProduct = new CProduct();
    }

    ~CConcreteBuilder1()
    {
        if (m_pProduct)
        {
            delete m_pProduct;
            m_pProduct = NULL;
        }
    }

    void BuildPartA()
    {
        m_pProduct->Add("部件A");
    }

    void BuildPartB()
    {
        m_pProduct->Add("部件B");
    }

    CProduct* GetResult()
    {
        return m_pProduct;
    }
};

// 具体建造者类
class CConcreteBuilder2 : public CBuilder
{
private:
    CProduct* m_pProduct;

public:
    CConcreteBuilder2()
    {
        m_pProduct = new CProduct();
    }

    ~CConcreteBuilder2()
    {
        if (m_pProduct)
        {
            delete m_pProduct;
            m_pProduct = NULL;
        }
    }
    void BuildPartA()
    {
        m_pProduct->Add("部件X");
    }

    void BuildPartB()
    {
        m_pProduct->Add("部件Y");
    }

    CProduct* GetResult()
    {
        return m_pProduct;
    }
};

// 指挥者类
class CDirector
{
public:
    void Construct(CBuilder* pBuilder)
    {
        pBuilder->BuildPartA();
        pBuilder->BuildPartB();
    }
};

int main()
{
    CDirector Director;
    CConcreteBuilder1 ConcreteBuilder1;
    CConcreteBuilder2 ConcreteBuilder2;

    Director.Construct(&ConcreteBuilder1);
    ConcreteBuilder1.GetResult()->Show();

    Director.Construct(&ConcreteBuilder2);
    ConcreteBuilder2.GetResult()->Show();

    system("pause");
    return 0;
}

输出结果：

例：画小人

代码如下：

#include <iostream>
#include <list>
#include <string>
using namespace std;

// 抽象建造者类
class CPersonBuilder
{
public:
    virtual void BuildHead() {};
    virtual void BuildBody() {};
    virtual void BuildArmLeft() {};
    virtual void BuildArmRight() {};
    virtual void BuildLegLeft() {};
    virtual void BuildLegRight() {};
};

// 具体建造者类
class CPersonThinBuilder : public CPersonBuilder
{
public:
    void BuildHead()
    {
        cout << "画瘦小人头" << endl;
    }

    void BuildBody()
    {
        cout << "画瘦小人身体" << endl;
    }

    void BuildArmLeft()
    {
        cout << "画瘦小人左臂" << endl;
    }

    void BuildArmRight()
    {
        cout << "画瘦小人右臂" << endl;
    }

    void BuildLegLeft()
    {
        cout << "画瘦小人左腿" << endl;
    }

    void BuildLegRight()
    {
        cout << "画瘦小人右腿" << endl;
    }
};

// 具体建造者类
class CPersonFatBuilder : public CPersonBuilder
{
public:
    void BuildHead()
    {
        cout << "画胖小人头" << endl;
    }

    void BuildBody()
    {
        cout << "画胖小人身体" << endl;
    }

    void BuildArmLeft()
    {
        cout << "画胖小人左臂" << endl;
    }

    void BuildArmRight()
    {
        cout << "画胖小人右臂" << endl;
    }

    void BuildLegLeft()
    {
        cout << "画胖小人左腿" << endl;
    }

    void BuildLegRight()
    {
        cout << "画胖小人右腿" << endl;
    }
};

// 指挥者类
class CPersonDirector
{
private:
    CPersonBuilder* m_pPerson;

public:
    CPersonDirector(CPersonBuilder* pPerson)
    {
        m_pPerson = pPerson;
    }

    void CreatePerson()
    {
        m_pPerson->BuildHead();
        m_pPerson->BuildBody();
        m_pPerson->BuildArmLeft();
        m_pPerson->BuildArmRight();
        m_pPerson->BuildLegLeft();
        m_pPerson->BuildLegRight();
    }
};

int main()
{
    CPersonThinBuilder Thin;
    CPersonDirector dThin(&Thin);
    dThin.CreatePerson();

    cout << "
华丽的分割线
" << endl;
    CPersonFatBuilder Fat;
    CPersonDirector dFat(&Fat);
    dFat.CreatePerson();

    system("pause");
    return 0;
}

输出结果：