builder.cpp

//将一个复杂对象的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。
//https://blog.csdn.net/naibozhuan3744/article/details/108230453
#include <iostream>
#include <string>

using namespace std;

#define DELETE(pointer) delete pointer; pointer=nullptr

class IProduct { //抽象产品类
public:
	virtual string& getName() = 0;
	virtual void show() = 0;
};

class Product1 : public IProduct { //具体产品类
public:
	string& getName() override { return name; }
	void show() override { cout << "name==" << name << endl; }

private:
	string name; //要构建的具体产品名字（分为多个步骤才能构建完毕）
};

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

	virtual void buildPart1() = 0;
	virtual void buildPart2() = 0;
	virtual IProduct* getProduuct() = 0;
};

class ConcreteBuilder : public IBuilder //构建具体结构，细节的具体实现或者说表示层
{
public:
	ConcreteBuilder(IProduct* product) : product(product) {}
	~ConcreteBuilder() {}

	void buildPart1() override { product->getName().append("buildPart1+"); }
	void buildPart2() override { product->getName().append("buildPart2"); }
	IProduct* getProduuct() override { return product; }

private:
	IProduct* product;
};

class Director //构建者，用表示层的细节实现接口函数按照一定逻辑组合成某一款产品
{
public:
	Director() {}
	~Director() {}


	IProduct* construct(IBuilder* builder) { //传入指针唯一目的是对该对象进行构建，构建前后指针地址一直不变
		builder->buildPart1();
		builder->buildPart2();
		return builder->getProduuct();
	}
};

void doBuilderPattern()
{
	IProduct* product = new Product1(); //创建一个初始化的产品
	IBuilder* builder = new ConcreteBuilder(product); //创建构造器，传入产品对象地址准备构造具体产品和功能
	Director().construct(builder); //构建具体产品和功能
	product->show();
	DELETE(builder);
	DELETE(product);
}

//int main()
//{
//	doBuilderPattern();
//
//	system("pause");
//	return 1;
//}