Java编程思想：利用内部类实现的工厂模式

public class Test {
    public static void main(String[] args) {
        Factories.test();
    }
}

/*
    设计模式之禅中的工厂模式是这样的，先定义好工厂和产品的接口，实现各个产品，
    产品无需为工厂编写任何代码。工厂通过传产品类的class对象来生成一个产品，这
    其中用到了反射方面的东西，我觉着这中方案会更好一点。

    案例中的方案，虽然利用接口降低了耦合，但是还是有点不太舒服
 */

interface Service {
    void method1();

    void method2();
}
interface ServiceFactory {
    Service getService();
}
class A implements Service {

    private A() {

    }

    @Override
    public void method1() {
        System.out.println("A method1");
    }

    @Override
    public void method2() {
        System.out.println("A method2");
    }

    public static ServiceFactory factory =
            new ServiceFactory() {
                @Override
                public Service getService() {
                    return new A();
                }
            };
}
class B implements Service {

    private B() {

    }

    @Override
    public void method1() {
        System.out.println("B method1");
    }

    @Override
    public void method2() {
        System.out.println("B method2");
    }

    public static ServiceFactory factory =
            new ServiceFactory() {
                @Override
                public Service getService() {
                    return new B();
                }
            };
}

class Factories{
    public static void serviceConsumer(ServiceFactory factory) {
        Service s = factory.getService();
        s.method1();
        s.method2();
    }

    public static void test() {
        serviceConsumer(A.factory);
        serviceConsumer(B.factory);
    }
}

public class Test {
    public static void main(String[] args) {
        Games.test();
    }
}

interface Game {
    boolean move();
}
interface GameFactory {
    Game getGame();
}
class Checkers implements Game{
    private Checkers() {};
    private int moves = 0;
    private static final int MOVES = 5;
    @Override
    public boolean move() {
        System.out.println("Checkers move " + move());
        return ++moves != MOVES;
    }

    public static GameFactory factory = new GameFactory() {
        @Override
        public Game getGame() {
            return new Checkers();
        }
    };
}
class Chess implements Game {
    private Chess() { }
    private int moves = 0;
    private static final int MOVES = 4;

    @Override
    public boolean move() {
        System.out.println("Chess move "+moves);
        return ++moves != MOVES;
    }

    public static GameFactory factory = new GameFactory() {
        @Override
        public Game getGame() {
            return new Chess();
        }
    };
}

public class Games {
    public static void playGame(GameFactory factory) {
        Game s = factory.getGame();
        while (s.move()) {

        }
    }

    public static void test() {
        playGame(Checkers.factory);
        playGame(Chess.factory);
    }
}