继承：工厂返回的类型一致；

多个if：对象获取

 Phone类：手机标准规范类(AbstractProduct)

public interface Phone {
    void make();
}

 MiPhone类：制造小米手机（Product1）

public class MiPhone implements Phone {
    public MiPhone() {
        this.make();
    }
    @Override
    public void make() {
        // TODO Auto-generated method stub
        System.out.println("make xiaomi phone!");
    }
}

IPhone类：制造苹果手机（Product2）

public class IPhone implements Phone {
    public IPhone() {
        this.make();
    }
    @Override
    public void make() {
        // TODO Auto-generated method stub
        System.out.println("make iphone!");
    }
}

PhoneFactory类：手机代工厂（Factory）

public class PhoneFactory {
    public Phone makePhone(String phoneType) {
        if(phoneType.equalsIgnoreCase("MiPhone")){
            return new MiPhone();
        }
        else if(phoneType.equalsIgnoreCase("iPhone")) {
            return new IPhone();
        }
        return null;
    }
}

 演示：

public class Demo {
    public static void main(String[] arg) {
        PhoneFactory factory = new PhoneFactory();
        Phone miPhone = factory.makePhone("MiPhone");            // make xiaomi phone!
        IPhone iPhone = (IPhone)factory.makePhone("iPhone");    // make iphone!
    }
}