抽象工厂模式是一种创建型设计模式，它提供了一种方式来封装一组具有共同主题的单独工厂。抽象工厂模式通过提供一个超级工厂创建其他工厂的接口，使得客户端使用抽象的接口操作具体对象，从而实现客户端与具体工厂类解耦。
使用C++实现抽象工厂模式（Abstract Factory）
下面是一个使用C++实现抽象工厂模式的例子：
#include <iostream>
#include <string>// 抽象产品A
class AbstractProductA {
public:virtual ~AbstractProductA() {}virtual std::string use() = 0;
};// 抽象产品B
class AbstractProductB {
public:virtual ~AbstractProductB() {}virtual std::string eat() = 0;
};// 具体产品A1
class ProductA1 : public AbstractProductA {
public:std::string use() override {return "Using Product A1";}
};// 具体产品A2
class ProductA2 : public AbstractProductA {
public:std::string use() override {return "Using Product A2";}
};// 具体产品B1
class ProductB1 : public AbstractProductB {
public:std::string eat() override {return "Eating Product B1";}
};// 具体产品B2
class ProductB2 : public AbstractProductB {
public:std::string eat() override {return "Eating Product B2";}
};// 抽象工厂
class AbstractFactory {
public:virtual ~AbstractFactory() {}virtual AbstractProductA* createProductA() = 0;virtual AbstractProductB* createProductB() = 0;
};// 具体工厂1
class Factory1 : public AbstractFactory {
public:AbstractProductA* createProductA() override {return new ProductA1();}AbstractProductB* createProductB() override {return new ProductB1();}
};// 具体工厂2
class Factory2 : public AbstractFactory {
public:AbstractProductA* createProductA() override {return new ProductA2();}AbstractProductB* createProductB() override {return new ProductB2();}
};// 客户端代码
void clientCode(AbstractFactory* factory) {AbstractProductA* productA = factory->createProductA();AbstractProductB* productB = factory->createProductB();std::cout << productA->use() << std::endl;std::cout << productB->eat() << std::endl;delete productA;delete productB;
}int main() {AbstractFactory* factory1 = new Factory1();AbstractFactory* factory2 = new Factory2();std::cout << "Using the products created by Factory 1:" << std::endl;clientCode(factory1);std::cout << "Using the products created by Factory 2:" << std::endl;clientCode(factory2);delete factory1;delete factory2;return 0;
}
运行结果如下所示：
在这个例子中，我们定义了两个抽象产品类AbstractProductA和AbstractProductB，以及两个具体产品类ProductA1和ProductA2、ProductB1和ProductB2。我们还定义了一个抽象工厂类AbstractFactory，以及两个具体工厂类Factory1和Factory2。
客户端代码使用抽象工厂接口来创建具体产品，并使用这些产品。通过使用抽象工厂模式，我们可以在不改变客户端代码的情况下，改变具体工厂类和具体产品类。
使用C#实现抽象工厂模式（Abstract Factory）
namespace Abstract_Factory_Pattern
{internal class Program{public interface ILaptop{void ShowSpecs();}public interface IDesktop{void ShowSpecs();}// Apple 品牌的产品public class AppleLaptop : ILaptop{public void ShowSpecs(){Console.WriteLine("Apple Laptop Specifications");}}public class AppleDesktop : IDesktop{public void ShowSpecs(){Console.WriteLine("Apple Desktop Specifications");}}// Lenovo 品牌的产品public class LenovoLaptop : ILaptop{public void ShowSpecs(){Console.WriteLine("Lenovo Laptop Specifications");}}public class LenovoDesktop : IDesktop{public void ShowSpecs(){Console.WriteLine("Lenovo Desktop Specifications");}}public interface IComputerFactory{ILaptop CreateLaptop();IDesktop CreateDesktop();}public class AppleFactory : IComputerFactory{public ILaptop CreateLaptop(){return new AppleLaptop();}public IDesktop CreateDesktop(){return new AppleDesktop();}}public class LenovoFactory : IComputerFactory{public ILaptop CreateLaptop(){return new LenovoLaptop();}public IDesktop CreateDesktop(){return new LenovoDesktop();}}static void Main(string[] args){// 创建工厂IComputerFactory appleFactory = new AppleFactory();IComputerFactory lenovoFactory = new LenovoFactory();// 创建 Apple 产品的笔记本和台式机ILaptop appleLaptop = appleFactory.CreateLaptop();IDesktop appleDesktop = appleFactory.CreateDesktop();appleLaptop.ShowSpecs();appleDesktop.ShowSpecs();// 创建 Lenovo 产品的笔记本和台式机ILaptop lenovoLaptop = lenovoFactory.CreateLaptop();IDesktop lenovoDesktop = lenovoFactory.CreateDesktop();lenovoLaptop.ShowSpecs();lenovoDesktop.ShowSpecs();}}
}
运行结果如下所示：
使用Java实现抽象工厂模式
package src.Design_Patterns;public class Abstract_Factory_Pattern
{public interface Laptop {void showSpecs();}public interface Desktop {void showSpecs();}// Apple 品牌的产品public class AppleLaptop implements Laptop {@Overridepublic void showSpecs() {System.out.println("Apple Laptop Specifications");}}public class AppleDesktop implements Desktop {@Overridepublic void showSpecs() {System.out.println("Apple Desktop Specifications");}}// Lenovo 品牌的产品public class LenovoLaptop implements Laptop {@Overridepublic void showSpecs() {System.out.println("Lenovo Laptop Specifications");}}public class LenovoDesktop implements Desktop {@Overridepublic void showSpecs() {System.out.println("Lenovo Desktop Specifications");}}public interface ComputerFactory {Laptop createLaptop();Desktop createDesktop();}public class AppleFactory implements ComputerFactory {@Overridepublic Laptop createLaptop() {return new AppleLaptop();}@Overridepublic Desktop createDesktop() {return new AppleDesktop();}}public class LenovoFactory implements ComputerFactory {@Overridepublic Laptop createLaptop() {return new LenovoLaptop();}@Overridepublic Desktop createDesktop() {return new LenovoDesktop();}}public void test(){// 创建工厂ComputerFactory appleFactory = new AppleFactory();ComputerFactory lenovoFactory = new LenovoFactory();// 创建 Apple 产品的笔记本和台式机Laptop appleLaptop = appleFactory.createLaptop();Desktop appleDesktop = appleFactory.createDesktop();appleLaptop.showSpecs();appleDesktop.showSpecs();// 创建 Lenovo 产品的笔记本和台式机Laptop lenovoLaptop = lenovoFactory.createLaptop();Desktop lenovoDesktop = lenovoFactory.createDesktop();lenovoLaptop.showSpecs();lenovoDesktop.showSpecs();}public static void main(String[] args) {Abstract_Factory_Pattern afp = new Abstract_Factory_Pattern();afp.test();}}
运行结果如下所示：
