桥接模式

2025-02-11 技术教程

在提出桥梁模式的时候指出，桥梁模式的用意是"将抽象化(Abstraction)与实现化(Implementation)脱耦，使得二者可以独立地变化"。这句话有三个关键词，也就是抽象化、实现化和脱耦。

抽象化存在于多个实体中的共同的概念性联系，就是抽象化。作为一个过程，抽象化就是忽略一些信息，从而把不同的实体当做同样的实体对待【LISKOV94】。实现化抽象化给出的具体实现，就是实现化。脱耦所谓耦合，就是两个实体的行为的某种强关联。而将它们的强关联去掉，就是耦合的解脱，或称脱耦。在这里，脱耦是指将抽象化和实现化之间的耦合解脱开，或者说是将它们之间的强关联改换成弱关联。

将两个角色之间的继承关系改为聚合关系，就是将它们之间的强关联改换成为弱关联。因此，桥梁模式中的所谓脱耦，就是指在一个软件系统的抽象化和实现化之间使用组合/聚合关系而不是继承关系，从而使两者可以相对独立地变化。这就是桥梁模式的用意。

在使用VIM 编写makefile时，有时TAP键会是八个空格，使用set list命令可以查看所有的TAB键是否正确。

makefile文件

aLL:BrigeCC = g++INCLUDE = .CFLAGS = -g -WallBrige:main.o CDrawLine.o CDrawSquare.o CSqureRefined.o CCircleRefined.o $(CC) -o Brige main.o CDrawLine.o CDrawSquare.o CSqureRefined.o CCircleRefined.oCDrawSquare.o:CDrawSquare.cpp CDrawSquare.h CImplement.cpp $(CC) -I$(INCLUDE) $(CFLAGS) -c CDrawSquare.cppCDrawLine.o:CDrawLine.cpp CDrawLine.h $(CC) -I$(INCLUDE) $(CFLAGS) -c CDrawLine.cppCSqureRefined.o:CSqureRefined.cpp CSqureRefined.h $(CC) -I$(INCLUDE) $(CFLAGS) -c CSqureRefined.cppCCircleRefined.o:CCircleRefined.cpp CCircleRefined.h $(CC) -I$(INCLUDE) $(CFLAGS) -c CCircleRefined.cppmain.o:main.cpp $(CC) -I$(INCLUDE) $(CFLAGS) -c main.cppclean: rm *.o rm Brige

CAbstraction.h

#ifndef CAbstractiongH#define CAbstractiongH#include<iostream>#include "CImplement.h"using namespace std;class CAbstractiong{public: virtual ~CAbstractiong(){}; virtual void Operation() = 0; void SetImplement(CImplement *tImplement){m_CImplement = tImplement;};protected: CAbstractiong(){}; CImplement *m_CImplement;};#endif

CCircleRefined

#ifndef CCircleRefinedH#define CCircleRefinedH#include "CAbstraction.h"class CCircleRefined:public CAbstractiong{public: CCircleRefined(){}; ~CCircleRefined(){}; void Operation(); };#endif#include "CCircleRefined.h"void CCircleRefined::Operation(){ cout<<"对圆形进行了"<<m_CImplement->Operation()<<endl;}

CSqureRefined

#ifndef CSqureRefinedH#define CSqureRefinedH#include "CAbstraction.h"class CSqureRefined:public CAbstractiong{public: CSqureRefined(){}; ~CSqureRefined(){}; void Operation(); };#endif#include "CSqureRefined.h"void CSqureRefined::Operation(){ cout<<"对正方形进行了"<<m_CImplement->Operation()<<endl;}

CAbstractiong

CDrawSquare

#ifndef CDrawSquareH#define CDrawSquareH#include<iostream>#include "CImplement.h"class CDrawSquare:public CImplement{public: CDrawSquare(){}; ~CDrawSquare(){}; string Operation(); };#endif#include "CDrawSquare.h"#include <iostream>using namespace std;string CDrawSquare::Operation(){ string sTemp ="进行了画方格操作"; return sTemp;}

CDrawLine

#ifndef CDrawLineH#define CDrawLineH#include<iostream>#include <string>#include "CImplement.h"class CDrawLine:public CImplement{public: CDrawLine(){}; ~CDrawLine(){}; string Operation(); };#endif#include "CDrawLine.h"#include <iostream>using namespace std;string CDrawLine::Operation(){ string sTemp = "进行了画线操作"; return sTemp;}

main.cpp

#include "CDrawLine.h"#include "CDrawSquare.h"#include "CSqureRefined.h"#include "CCircleRefined.h"int main(){ CDrawLine *pCDrawLine = new CDrawLine(); CCircleRefined *pCCircleRefined = new CCircleRefined(); pCCircleRefined->SetImplement(pCDrawLine); pCCircleRefined->Operation(); CDrawSquare *pCDrawSquare = new CDrawSquare(); pCCircleRefined->SetImplement(pCDrawSquare); pCCircleRefined->Operation(); return 0;}