抽象工厂模式(abstract factory)

意图：提供一个创建一系列相关或相互依赖对象的接口，而无需指定它们具体的类
结构：

AbstractFactory声明一个创建抽象产品的操作接口
ConcreteFactory实现创建具体产品对象的操作
AbstractProduct为一类产品对象声明一个接口
ConcreteProduct定义一个将被相应的具体工厂创建的产品对象，并且要实现AbstractProduct接口

实现示例：

public abstract class ProductA {
	abstract void operationA();
}

public abstract class ProductB {
	abstract void operationB();
}

ublic abstract class AbstractFactory {
	abstract ProductA getProductA();
	abstract ProductB getProductB();
}

public class ProductA1 extends ProductA {
	@Override
	void operationA() {
		System.out.println("ProductA1 operation A1");
	}
}

public class ProductB1 extends ProductB {
	@Override
	void operationB() {
		System.out.println("ProductB1 operation B1");
	}
}

public class ConcreteFactory1 extends AbstractFactory {
	@Override
	ProductA getProductA() {
		return new ProductA1();
	}

	@Override
	ProductB getProductB() {
		return new ProductB1();
	}
}

public class ProductA2 extends ProductA {
	@Override
	void operationA() {
		System.out.println("ProductA2 operation A2");
	}
}

ublic class ProductB2 extends ProductB {
	@Override
	void operationB() {
		System.out.println("ProductB2 operation B2");
	}
}

public class ConcreteFactory2 extends AbstractFactory {
	@Override
	ProductA getProductA() {
		// TODO Auto-generated method stub
		return new ProductA2();
	}

	@Override
	ProductB getProductB() {
		// TODO Auto-generated method stub
		return new ProductB2();
	}
}

客户端使用代码：

public class Client {
	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		System.out.println(args[0]);
		AbstractFactory f = null;
		switch (Integer.parseInt(args[0])) {
		case 1:
			System.out.println("select 1 series Factory");
			f = new ConcreteFactory1();
			break;
		case 2:
			System.out.println("select 2 series Factory");
			f = new ConcreteFactory2();
			break;
		default:
			System.out.println("wrong command parameter");
			System.exit(2);
		}
		ProductA pa = f.getProductA();
		ProductB pb = f.getProductB();
		pa.operationA();
		pb.operationB();
	}
}

运行结果：
命令行参数 1 时的结果：
1
select 1 series Factory
ProductA1 operation A1
ProductB1 operation B1

命令行参数 2时的结果：
2
select 2 series Factory
ProductA2 operation A2
ProductB2 operation B2