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OO设计模式_抽象工厂模式

Motivation

在软件系统中，经常面临着“一系列相互依赖的对象”的创建工作;同时，由于需求变化，往往存在更多系列对象的创建工作。

如何对应这种变化？如果绕过常规的对象创建方法（New）,提供一种“封装机制”来避免客户程序和这种“多系列具体对象创建工作”的紧耦合。

Intent

提供一个接口，让该接口负责创建一系列“相关或者相互依赖的对象”，无需指定他们的具体的类。

Structure

OO设计模式_抽象工厂模式

Code：

abstract class FacilityFactory {  abstract Road CreateRoad();  abstract Road CreateBuilding();  abstract Road CreateJungle(); } class ModernFacilityFactory {  override Road CreateRoad()  {   return new ModernRoad();   }  abstract Road CreateBuilding()   {   return new ModernBuilding();  }  abstract Road CreateJungle()  {   return new ModernJungle();  } } class ClassicFacilityFactory {  override Road CreateRoad()  {   return new ClassicRoad();   }  abstract Road CreateBuilding()   {   return new ClassicBuilding();  }  abstract Road CreateJungle()  {   return new ClassicJungle();  } } abstract class Road { } class ModernRoad : Road { } class ClassicRoad : Road { } abstract class Building { } class ModernBuilding : Building { } class ClassicBuilding : Building { } abstract class Jungle { } class ModernJungle : Jungle { } class ClassicJungle : Jungle { } class App {  Road road;  Building building;  Jungle jungle;  public static void Main()  {   FacilityFactory modernFacilityFactory=new ModernFacilityFactory();   Road road = modernFacilityFactory.CreateRoad();   building = modernFacilityFactory.CreateBuilding();   jungle = modernFacilityFactory.CreateJungle();  } }