【多态案例】电脑组装

案例描述

电脑主要组成部件为 CPU（用于计算），显卡（用于显示），内存条（用于存储）。

将每个零件封装出抽象基类，并且提供不同的厂商生产不同的零件，例如Intel厂商和Lenovo厂商。

创建电脑类提供让电脑工作的函数，并且调用每个零件工作的接口。

测试时组装三台不同的电脑进行工作。

代码

#include<iostream>
using namespace std;

//抽象CPU类
class CPU
{
public:
	//抽象计算函数
	virtual void calculate() = 0;
};
//抽象显卡类
class VideoCard
{
public:
	//抽象显示函数
	virtual void display() = 0;
};
//抽象内存条类
class Memory
{
public:
	//抽象存储函数
	virtual void storage() = 0;
};

//电脑类
class Computer
{
public:
	Computer(CPU* cpu, VideoCard* vc, Memory* mem)
	{
		m_cpu = cpu;
		m_vc = vc;
		m_mem = mem;
	}
	//工作函数
	void work()
	{
		//让零件工作起来，调用接口
		m_cpu->calculate();
		m_vc->display();
		m_mem->storage();
	}
	//提供析构函数  释放3个堆区零件
	~Computer()
	{
		//释放CPU零件
		if (m_cpu != NULL)
		{
			delete m_cpu;
			m_cpu = NULL;
		}
		//释放显卡零件
		if (m_vc != NULL)
		{
			delete m_vc;
			m_vc = NULL;
		}
		//释放内存条零件
		if (m_mem != NULL)
		{
			delete m_mem;
			m_mem = NULL;
		}
	}

private:
	CPU* m_cpu;//CPU零件指针
	VideoCard* m_vc;//显卡零件指针
	Memory* m_mem;//内存条零件指针
};

//具体厂商
//Intel厂商
class IntelCPU :public CPU
{
public:
	virtual void calculate()
	{
		cout << "Intel的CPU开始计算了" << endl;
	}
};
class IntelVideoCard :public VideoCard
{
public:
	virtual void display()
	{
		cout << "Intel的显卡开始显示了" << endl;
	}
};
class IntelMemory :public Memory
{
public:
	virtual void storage()
	{
		cout << "Intel的内存条开始存储了" << endl;
	}
};
//Lenovo厂商
class LenovoCPU :public CPU
{
public:
	virtual void calculate()
	{
		cout << "Lenovo的CPU开始计算了" << endl;
	}
};
class LenovoVideoCard :public VideoCard 
{
public:
	virtual void display()
	{
		cout << "Lenovo的显卡开始显示了" << endl;
	}
};
class LenovoMemory :public Memory
{
public:
	virtual void storage()
	{
		cout << "Lenovo的内存条开始存储了" << endl;
	}
};

void test01()
{
	
	//第一台电脑零件
	CPU* intelCPU = new IntelCPU;
	VideoCard* intelVideoCard = new IntelVideoCard;
	Memory* intelMemory = new IntelMemory;

	cout << "第一台电脑：" << endl;
	//创建第一台电脑
	Computer* computer1 = new Computer(intelCPU, intelVideoCard, intelMemory);
	computer1->work();
	delete computer1;

	cout << "------------------------" << endl;
	cout << "第二台电脑：" << endl;

	//省略创建零件步骤
	//创建第二台电脑
	Computer* computer2 = new Computer(new LenovoCPU, new LenovoVideoCard, new LenovoMemory);
	computer2->work();
	delete computer2;

	cout << "------------------------" << endl;
	cout << "第三台电脑：" << endl;

	//省略创建零件步骤
	//创建第三台电脑
	Computer* computer3 = new Computer(new LenovoCPU, new IntelVideoCard, new LenovoMemory);
	computer3->work();
	delete computer3;
}

int main()
{
	test01();
	system("pause");
	return 0;
}

测试