[设计模式]<2>. C++与生成器模式(Builder pattern)

原文地址：

http://www.cnblogs.com/hebaichuanyeah/p/5585957.html

当构建一个复杂对象时，将构建过程与表示分离。使得同样的过程创建不同的对象。

简单例子，构建produce类，需要构建三个部分part1，part2，part3。通过build类去构建它们，并返回。通过director 类调用build对象进行配置。

C++代码

#include <iostream>

using namespace std;

class Produce
{
public:
    Produce(){}
    virtual ~Produce(){}

};

class Builder
{
public:
    Builder(){}
    virtual ~Builder(){}

    virtual void BuildPart1(){}
    virtual void BuildPart2(){}
    virtual void BuildPart3(){}
    virtual Produce * GetProduce(){}

};

class ProduceBuilder:public Builder
{
private:
Produce * produce;
public:
    ProduceBuilder(){}

    virtual void BuildPart1()
    {
        produce = new Produce();
        cout<<"bulid part1"<<endl;
        //填充构建part1部分
    }
    virtual void BuildPart2()
    {
        cout<<"bulid part2"<<endl;
        //填充构建part2部分
    }
    virtual void BuildPart3()
    {
        cout<<"bulid part3"<<endl;
        //填充构建part3部分
    }
    virtual Produce * GetProduce()
    {
        return produce;
    }

};

class Director
{
private:
    Builder * bulider;
public:
    Director(Builder * builder)
    {
        bulider = builder;
    }
    void construct()
    {
        bulider->BuildPart1();
        bulider->BuildPart2();
        bulider->BuildPart3();
    }
};
main()
{
    Produce * produce;
    Builder * bulider  = new ProduceBuilder();
    Director * myDirector = new Director(bulider);
    myDirector->construct();
    produce = bulider->GetProduce();
}