设计模式入门：抽象工厂模式

/**
 * 苹果抽象类
 */
public interface IApple {

    /**
     * 具体描述
     */
    void describe();

}

/**
 * 红苹果
 */
public class RedApple implements IApple {

    @Override
    public void describe() {
        System.out.println("This is red apple");
    }

}

/**
 * 青苹果
 */
public class GreenApple implements IApple {

    @Override
    public void describe() {
        System.out.println("This is green apple");
    }

}

/**
 * 梨子抽象类
 */
public interface IPear {

    /**
     * 具体描述
     */
    void describe();

}

/**
 * 青梨
 */
public class GreenPear implements IPear {

    @Override
    public void describe() {
        System.out.println("This is green pear");
    }

}

/**
 * 黄梨
 */
public class YellowPear implements IPear {

    @Override
    public void describe() {
        System.out.println("This is yellow pear");
    }

}

/**
 * 水果工厂抽象类
 */
public interface IFruitFactory {

    /**
     * 创建苹果实例
     *
     * @return
     */
    IApple createApple();

    /**
     * 创建梨子实例
     *
     * @return
     */
    IPear createPear();

}

/**
 * 工厂A: 负责生产青苹果和青梨
 */
public class FactoryA implements IFruitFactory {

    @Override
    public IApple createApple() {
        return new GreenApple();
    }

    @Override
    public IPear createPear() {
        return new GreenPear();
    }

}

/**
 * 工厂B: 负责生产红苹果和黄梨
 */
public class FactoryB implements IFruitFactory {

    @Override
    public IApple createApple() {
        return new RedApple();
    }

    @Override
    public IPear createPear() {
        return new YellowPear();
    }

}

public class Main {

    public static void main(String[] args) {
        IFruitFactory factoryA = new FactoryA();
        IApple apple = factoryA.createApple();
        apple.describe();
        IPear pear = factoryA.createPear();
        pear.describe();

        System.out.println("-------------------");

        IFruitFactory factoryB = new FactoryB();
        apple = factoryB.createApple();
        apple.describe();
        pear = factoryB.createPear();
        pear.describe();
    }

}