【java】工厂模式Factory，利用反射改进

package 反射;
interface Product{
    public void produce();
}
class socks implements Product{
    @Override
    public void produce() {
        System.out.println("袜子被生产");
    }
}
/*
class shoes implements Product{
    @Override
    public void produce() {
        System.out.println("鞋子被生产");
    }
}
*/
class Factory{
    private static Product product;
    public static Product getInstance(String productName){
        if(productName.equals("袜子"))
            product=new socks();
        /*每添加一个产品就得增加getInstance方法的代码，可以利用反射改写
        if(productName.equals("鞋子"))
            product=new shoes();
        */
        return product;
    }
}
public class TestFactory {
    public static void main(String[] args) {
        Product product=Factory.getInstance("袜子");
        product.produce();//袜子被生产
        /*
        Product product2=Factory.getInstance("鞋子");
        product2.produce();//鞋子被生产
        */
    }
}

package 反射;
interface Product{
    public void produce();
}
class socks implements Product{
    @Override
    public void produce() {
        System.out.println("袜子被生产");
    }
}

class shoes implements Product{
    @Override
    public void produce() {
        System.out.println("鞋子被生产");
    }
}

class Factory{
    private static Product product;
    public static Product getInstance(String productName) throws ClassNotFoundException, InstantiationException, IllegalAccessException{
        Class<?> cls=Class.forName(productName);
        product=(Product)cls.newInstance();
        return product;
    }
}
public class TestFactory {
    public static void main(String[] args) throws ClassNotFoundException, InstantiationException, IllegalAccessException {
        Product product=Factory.getInstance("反射.socks");
        product.produce();//袜子被生产
        
        Product product2=Factory.getInstance("反射.shoes");
        product2.produce();//鞋子被生产
        
    }
}