工厂模式

一、工厂模式

二、简单工厂

图解

示例代码

#include <iostream>

using namespace std;

enum CpuType
{
    CoreA, CoreB, CoreC
};

class Cpu
{
public:
    virtual void work() = 0;
};

class SingleCoreA : public Cpu
{
public:
    void work()
    {
        cout << "SingleCoreA work()" << endl;
    }
};

class SingleCoreB : public Cpu
{
public:
    void work()
    {
        cout << "SingleCoreB work()" << endl;
    }
};

class Factory
{
public:
    Cpu * createCpu(enum CpuType type)
    {
        if (type == CoreA) return new SingleCoreA;
        else if (type == CoreB) return new SingleCoreB;
    }
};

int main()
{
    Factory fac;
    Cpu *pCpu = fac.createCpu(CoreA);
    pCpu->work();

    pCpu = fac.createCpu(CoreB);
    pCpu->work();


    return 0;
}

三、复杂工厂

图解

#include <iostream>

using namespace std;
enum CpuType
{
    CoreA, CoreB, CoreC
};

class Cpu
{
public:
    virtual void work() = 0;
};

class SingleCoreA : public Cpu
{
public:
    void work()
    {
        cout << "SingleCoreA work()" << endl;
    }
};

class SingleCoreB : public Cpu
{
public:
    void work()
    {
        cout << "SingleCoreB work()" << endl;
    }
};

class Factory
{
public:
    virtual Cpu* createCpu() = 0;
};

class FactoryA : public Factory
{
public:
    Cpu* createCpu()
    {
        return new SingleCoreA;
    }
};

class FactoryB : public Factory
{
public:
    Cpu* createCpu()
    {
        return new SingleCoreB;
    }
};


int main()
{
    FactoryA fa;

    Cpu* pCpu = fa.createCpu();
    pCpu->work();

    FactoryB fb;
    pCpu = fb.createCpu();
    pCpu->work();

    return 0;
}