设计模式学习小结（2.2）——桥接模式

作用：

应对当前多种多样的操作系统，程序可能需要多套接口，并随时有可能新增接口。将逻辑和实现分离，使程序可以十分方便的扩展。

示例代码：

Logic.h

#ifndef _LOGIC_H_
#define _LOGIC_H_

/*****************************************************************************
* 稳定的对外接口
* 如果需要新增实现
* 只需增加新增一个AbstractRealize类的实例即可
*****************************************************************************/

class AbstractRealize;

class Logic
{
public:
Logic(AbstractRealize* realize);
~Logic(void);
void Operation();
private:
AbstractRealize* m_realize;
};

#endif

Logic.cpp

#include "Logic.h"
#include "Realize.h"

Logic::Logic( AbstractRealize* realize )
{
m_realize = realize;
}

Logic::~Logic(void)
{
if (NULL != m_realize)
{
delete m_realize;
}
}

void Logic::Operation()
{
m_realize->Operation();
}

Realize.h

#ifndef _REALIZE_H_
#define _REALIZE_H_

#include <iostream>

using namespace std;

/*****************************************************************************
* 对应各系统的具体实现
*****************************************************************************/

class AbstractRealize
{
public:
virtual ~AbstractRealize();
virtual void Operation() = 0;
protected:
AbstractRealize();
};

class RealizeWinXP : public AbstractRealize
{
public:
RealizeWinXP(void);
~RealizeWinXP(void);
void Operation();
};

class RealizeLinux : public AbstractRealize
{
public:
RealizeLinux(void);
~RealizeLinux(void);
void Operation();
};

#endif

Realize.cpp

#include "Realize.h"

AbstractRealize::AbstractRealize()
{

}

AbstractRealize::~AbstractRealize()
{

}

RealizeWinXP::RealizeWinXP( void )
{

}

RealizeWinXP::~RealizeWinXP( void )
{

}

void RealizeWinXP::Operation()
{
cout<<"Windows XP Operation"<<endl;
}

RealizeLinux::RealizeLinux( void )
{

}

RealizeLinux::~RealizeLinux( void )
{

}

void RealizeLinux::Operation()
{
cout<<"Linux Operation"<<endl;
}

cilent.cpp

#include "Logic.h"
#include "Realize.h"
#include <iostream>

void main()
{
AbstractRealize* realizeXP = new RealizeWinXP();
AbstractRealize* realizeLinux = new RealizeLinux();
Logic* l1 = new Logic(realizeXP);
l1->Operation();
Logic* l2 = new Logic(realizeLinux);
l2->Operation();
delete l1;
delete l2;
system("pause");
}

如果要新增安卓系统的接口，只需新增一个AbstractRealize类的派生类即可。