簡單工廠模式屬于創建型的設計模式,其特點是使用一個工廠生產所有的類對象,通過在工廠類中進行判斷，然后創建需要的功能類。 優點:不必使用具體的功能類去創建該類的實例。 缺點:新增一個功能類就需要在工廠類中增加一個判斷。
此處利用”+”,”-“,”*”,”/”這4個Operation來生成不同的Operation對象來說明簡單工廠模式。
文件構成： —include ——Operation.h ——Add.h ——Subtraction.h ——Multiply.h ——Division.h ——OperationFactory.h —src ——Add.cpp ——Subtraction.cpp ——Multiply.cpp ——Division.cpp ——OperationFactory.cpp ——main.cpp 代碼如下： —include/Operation.h
#ifndef _OPERATION_H_#define _OPERATION_H_class Operation{public: virtual double GetResult(double A, double B)=0;};#endif—include/Add.h
#ifndef _ADD_H_#define _ADD_H_#include"Operation.h"class Add:public Operation{public: double GetResult(double A, double B);};#endif—include/Subtraction.h
#ifndef _SUBTRACTION_H_#define _SUBTRACTION_H_#include"Operation.h"class Subtraction:public Operation{public: double GetResult(double A, double B);};#endif—include/Multiply.h
#ifndef _MULTIPLY_H_#define _MULTIPLY_H_#include"Operation.h"class Multiply:public Operation{public: double GetResult(double A, double B);};#endif—include/Division.h
#ifndef _DIVISION_H_#define _DIVISION_H_#include"Operation.h"class Division:public Operation{public: double GetResult(double A, double B);};#endif—include/OperationFactory.h
#ifndef _OPERATIONFACTORY_H_#define _OPERATIONFACTORY_H_#include"Add.h"#include"Subtraction.h"#include"Multiply.h"#include"Division.h"class OperationFactory{public: static Operation* CreateOperation(char opertionType);};#endif—src/Add.cpp
#include"Add.h"double Add::GetResult(double A, double B){ return A+B;}—src/Subtraction.cpp
#include"Subtraction.h"double Subtraction::GetResult(double A, double B){ return A-B;}—src/Multiply.cpp
#include"Multiply.h"double Multiply::GetResult(double A, double B){ return A*B;}—src/Division.cpp
#include"Division.h"double Division::GetResult(double A, double B){ return A/B;}—src/OperationFactory.cpp
#include<iostream>#include"OperationFactory.h"using namespace std;Operation* OperationFactory::CreateOperation(char operationType){ Operation* op=NULL; switch(operationType) { case '+': op=new Add(); break; case '-': op=new Subtraction(); break; case '*': op=new Multiply(); break; case '/': op=new Division(); break; default: break; } return op;}—src/main.cpp
#include<iostream>#include"OperationFactory.h"#include"Operation.h"using namespace std;int main(){ double value1=8; double value2=2; Operation *addOperator=OperationFactory::CreateOperation('+'); Operation *subOperator=OperationFactory::CreateOperation('-'); Operation *mulOperator=OperationFactory::CreateOperation('*'); Operation *divOperator=OperationFactory::CreateOperation('/'); cout<<"Add Operation: "<<value1<<" "<<value2<<" "<<addOperator->GetResult(value1,value2)<<endl; cout<<"Subtraction Operation: "<<value1<<" "<<value2<<" "<<subOperator->GetResult(value1,value2)<<endl; cout<<"Multiply Operation: "<<value1<<" "<<value2<<" "<<mulOperator->GetResult(value1,value2)<<endl; cout<<"Division Operation: "<<value1<<" "<<value2<<" "<<divOperator->GetResult(value1,value2)<<endl; delete addOperator; delete subOperator; delete mulOperator; delete divOperator; return 0;}文件構成： —Operation.py —OperationFactory.py 代碼如下： —Operation.py
#-*- coding:utf-8 -*-class Operation: def GetResult(self, A, B): passclass Add(Operation): def GetResult(self, A, B): return A+Bclass Subtraction(Operation): def GetResult(self, A, B): return A-Bclass Multiply(Operation): def GetResult(self, A, B): return A*Bclass Division(Operation): def GetResult(self, A, B): return A/B—OperationFactory.py
# -*- coding:utf-8 -*-from Operation import *class OperationFactory: @staticmethod def CreateOperation(operationType): if operationType == "+": return Add() elif operationType == "-": return Subtraction() elif operationType == "*": return Multiply() elif operationType == "/": return Division() else: return Noneif "__main__" == __name__: AddOp = OperationFactory.CreateOperation("+") SubOp = OperationFactory.CreateOperation("-") MulOp = OperationFactory.CreateOperation("*") DivOp = OperationFactory.CreateOperation("/") value1 = 8. value2 = 2.新聞熱點
疑難解答
