工厂模式

心得：说白了工厂模式就是集中管理其它类示例的场所，根据是否满足开闭原则分为简单工厂模式和(工厂方法模式，抽象工厂模式)

1:简单工厂模式

示例代码如下：

public class CeShi {
    public static void main(String[] args) {
        FruitFactory fruitFactory=new FruitFactory();
        Fruit apple=fruitFactory.getApple("中国");
        Fruit orange=fruitFactory.getOrange("美国");
        System.out.println(apple.getData());
        System.out.println(orange.getData());
    }
}

public class FruitFactory {
    public Fruit getApple(String address){
        return new Apple(address);
    }
    public Fruit getOrange(String address){
        return new Orange(address);
    }
}

public abstract class Fruit {
    protected String address;
    public abstract String getData();
}

public class Apple extends Fruit {
    public Apple(String address) {
        this.address=address;
    }

    @Override
    public String getData() {
        return "我是来自"+address+"的苹果";
    }
}

public class Orange extends Fruit{
        public Orange(String address) {
            this.address=address;
        }

        @Override
        public String getData() {
            return "我是来自"+address+"的橘子";
        }
}

输出结果:
我是来自中国的苹果
我是来自美国的橘子

2:工厂方法模式(相比较于简单工厂模式，符合开闭原则，对扩展开放，对修改封闭)

示例代码如下：

public class CeShi {
    public static void main(String[] args) {
        AppleFactory appleFactory=new AppleFactory();
        OrangeFactory orangeFactory=new OrangeFactory();
        Fruit fruit=appleFactory.getFruit("中国");
        Fruit fruit1=orangeFactory.getFruit("美国");
        System.out.println(fruit.getData());
        System.out.println(fruit1.getData());
    }
}

public interface FruitFactory {
    public Fruit getFruit(String address);
}

public class AppleFactory implements FruitFactory {
    @Override
    public Fruit getFruit(String address) {
        return new Apple(address);
    }
}

public class OrangeFactory implements FruitFactory{
    @Override
    public Fruit getFruit(String address) {
        return new Orange(address);
    }
}

public abstract class Fruit {
    protected String address;
    public abstract String getData();
}

public class Apple extends Fruit {
    public Apple(String address) {
        this.address=address;
    }

    @Override
    public String getData() {
        return "我是来自"+address+"的苹果";
    }
}

public class Orange extends Fruit{
        public Orange(String address) {
            this.address=address;
        }

        @Override
        public String getData() {
            return "我是来自"+address+"的橘子";
        }
}

输出结果:
我是来自中国的苹果
我是来自美国的橘子

3:抽象工厂模式

示例代码如下：

public class CeShi {
    public static void main(String[] args) {
        ChinaFactory chinaFactory=new ChinaFactory();
        Food food=chinaFactory.createFood("辣条");
        Fruit fruit=chinaFactory.createFruit("苹果");
        USAFactory usaFactory=new USAFactory();
        Food food1=usaFactory.createFood("薯片");
        Fruit fruit1=usaFactory.createFruit("橘子");
        System.out.println(food.getData());
        System.out.println(fruit.getData());
        System.out.println(food1.getData());
        System.out.println(fruit1.getData());
    }
}

public interface Factory {
    public Fruit createFruit(String name);
    public Food createFood(String name);
}

public class USAFactory implements Factory {
    @Override
    public Fruit createFruit(String name) {
        return new USAFruit(name);
    }

    @Override
    public Food createFood(String name) {
        return new USAFood(name);
    }
}

public class ChinaFactory implements Factory {
    @Override
    public Fruit createFruit(String name) {
        return new ChinaFruit(name);
    }

    @Override
    public Food createFood(String name) {
        return new ChinaFood(name);
    }
}

public class USAFood extends Food {
    public USAFood(String name) {
        this.name=name;
    }

    @Override
    public String getData() {
        return "我是来自美国的"+name;
    }
}

public class USAFruit extends Fruit{
    public USAFruit(String name) {
        this.name=name;
    }

    @Override
    public String getData() {
        return "我是来自美国的"+name;
    }
}

public class ChinaFood extends Food {
    public ChinaFood(String name) {
        this.name=name;
    }

    @Override
    public String getData() {
        return "我是来自中国的"+name;
    }
}

public class ChinaFruit extends Fruit{
    public ChinaFruit(String name) {
        this.name=name;
    }

    @Override
    public String getData() {
        return "我是来自中国的"+name;
    }
}

输出结果:
我是来自中国的辣条
我是来自中国的苹果
我是来自美国的薯片
我是来自美国的橘子

最后来张大神做的图

简单工厂模式
工厂方法模式
抽象工厂模式
参考文章
https://www.jianshu.com/p/750b82fa6a62
http://zyjustin9.iteye.com/blog/2094960(这篇博客总结的也很好)