工厂模式

1：工厂方法模式：

public class FactoryTest {

    //定义抽象产品类
    public abstract class Phone {
        public abstract String brandName();
    }

    //定义具体实现类
    public class Huawei extends Phone {

        @Override
        public String brandName() {
            return "my name is Huawei";
        }
    }

    //定义具体实现类
    public class Xiaomi extends Phone {

        @Override
        public String brandName() {
            return "my name is Xiaomi";
        }
    }

    //定义抽象工厂
    public abstract class Factory {
        public abstract Phone generatePhone();
    }

    //定义Huawei工厂,生成华为手机
    public class HuaweiFactory extends Factory {

        @Override
        public Phone generatePhone() {
            return new Huawei();
        }
    }

    //定义Xiaomi工厂,生成小米手机
    public class XiaomiFactory extends Factory {

        @Override
        public Phone generatePhone() {
            return new Huawei();
        }
    }

    //使用：
    public void test() {
        Factory huaweiFactory = new HuaweiFactory();
        Phone huaweiPhone = huaweiFactory.generatePhone();
        Log.d("test", "phone name--->" + huaweiPhone.brandName());

        Factory xiaomiFactory = new XiaomiFactory();
        Phone xiaomiPhone = xiaomiFactory.generatePhone();
        Log.d("test", "phone name--->" + xiaomiPhone.brandName());
    }
}

改进：

public class FactoryTest {

    //定义抽象产品类
    public abstract class Phone {
        public abstract String brandName();
    }

    //定义具体实现类
    public class Huawei extends Phone {

        @Override
        public String brandName() {
            return "my name is Huawei";
        }
    }

    //定义具体实现类
    public class Xiaomi extends Phone {

        @Override
        public String brandName() {
            return "my name is Xiaomi";
        }
    }

    //定义抽象工厂
    public abstract class Factory {
        public abstract <T extends Phone> T generatePhone(Class<T> tClass);
    }

    //具体工厂
    public class ConcretFactory extends Factory {

        @Override
        public <T extends Phone> T generatePhone(Class<T> tClass) {
            Phone phone = null;
            try {
                phone = (Phone) Class.forName(tClass.getName()).newInstance();
                Log.e("test", "生产了一个手机");
                phone.brandName();
            } catch (Exception e) {

            }
            return (T) phone;

        }
    }


    //使用：
    public void test() {
        Phone huaweiPhone = new ConcretFactory().generatePhone(Huawei.class);
        huaweiPhone.brandName();
    }
}