静态工厂，普通工厂，抽象工厂---创建型设计模式

一、静态工厂（简单，但是增加多一个对象时要修改代码）

工厂代码

public class StaFactory {
    private static StaFactory ourInstance = new StaFactory();

    public static StaFactory getInstance() {
        return ourInstance;
    }

    private StaFactory() {
    }

    public Animal getAnimal(String annimal){
        switch (annimal){
            case ("cat"):return new Cat();

            case ("dog"):return new Dog();

            default:return null;
        }
    }
}

客户端代码

    public static void main(String[] args) {
        Animal dog = StaFactory.getInstance().getAnimal("dog");
        dog.run();
        Animal cat = StaFactory.getInstance().getAnimal("cat");
        cat.run();
    }

二、普通工厂（增加对象时不用修改代码，但是要增加很多class文件）

　　只贴一个工厂的例子

public class DogFactory {
    private static DogFactory ourInstance = new DogFactory();

    public static DogFactory getInstance() {
        return ourInstance;
    }

    private DogFactory() {
    }
    public Animal Create(){
        return new Dog();
    }
}

客户端使用

 //普通工厂
    public static void main(String[] args) {
        Animal dog = DogFactory.getInstance().Create();
        dog.run();
        Animal cat = CatFactory.getInstance().Create();
        cat.run();
    }

三、抽象工厂，基本上是普通工厂的升级，只是多几个create方法

先写一个工厂接口

public interface AbFactory {
     Person createPerson();
     Animal createAnimal();
}

再写一个工厂实例

public class HighFactory implements AbFactory {
    @Override
    public Person createPerson() {
        return new HighPerson();
    }

    @Override
    public Animal createAnimal() {
        return new HighAnimal();
    }
}

客户端调用代码

    //客户端调用代码
    public static void main(String[] args) {
        HighFactory highFactory = new HighFactory();
        highFactory.createAnimal().run();
        highFactory.createPerson().say();
    }