【初学设计模式】Builder (生成器)

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类图：

 

 

 

代码实现：

 

头声明：

/********************************************************************File: builder.hAuthor:blackboy [e-mail]:生成器模式Created:2011-03-15Modified:2011-03-16 15:40*********************************************************************/#ifndef __BUILDER_H__#define __BUILDER_H__namespace blackboycpp{ class ProductA; class ProductB; class Builder; ////////////////////////////////////////////////////////////////////////// // Director class Director { public: void Construct(Builder* builder); }; ////////////////////////////////////////////////////////////////////////// // Builders class Builder { public: // 注意，以下2函数不能声明为纯虚函数，这样派生类可以不必非得实现 virtual void BuildPartA(); virtual void BuildPartB(); }; class ConcreteBuilderA : public Builder { public: ConcreteBuilderA(); public: virtual void BuildPartA(); virtual void BuildPartB(); virtual ProductA* GetProductA() { return _productA; } private: ProductA* _productA; }; class ConcreteBuilderB : public Builder { public: ConcreteBuilderB(); public: virtual void BuildPartA(); virtual ProductB* GetProductB() { return _productB; } private: ProductB* _productB; }; ////////////////////////////////////////////////////////////////////////// // Products class ProductA { }; class ProductB { }; }#endif

 

类实现：

#include <iostream>#include "builder.h"namespace blackboycpp{ void Director::Construct(Builder* builder) { std::cout << "Director::Construct(Builder*)/n"; builder->BuildPartA(); builder->BuildPartB(); } void Builder::BuildPartA() { std::cout << "Builder::BuildPartA()/n"; } void Builder::BuildPartB() { std::cout << "Builder::BuildPartB()/n"; } ConcreteBuilderA::ConcreteBuilderA() { std::cout << "ConcreteBuilderA::ConcreteBuilderA()/n"; _productA = new ProductA; } void ConcreteBuilderA::BuildPartA() { std::cout << "ConcreteBuilderA::BuildPartA()/n"; } void ConcreteBuilderA::BuildPartB() { std::cout << "ConcreteBuilderA::BuildPartB()/n"; } ConcreteBuilderB::ConcreteBuilderB() { std::cout << "ConcreteBuilderB::ConcreteBuilderB()/n"; _productB = new ProductB; } void ConcreteBuilderB::BuildPartA() { std::cout << "ConcreteBuilderB::BuildPartA()/n"; }}

 

 

main()：

#include <cstdlib>#include "builder.h"using namespace blackboycpp;int main(int argc, char** argv){ Director* director = new Director; ConcreteBuilderA* builderA = new ConcreteBuilderA; director->Construct(builderA); ProductA* productA = builderA->GetProductA(); delete productA; delete builderA; delete director; system("pause"); return 0;}