drhs13583567608 2012-02-07 18:17
浏览 34

Kohana 3中空抽象类的目的是什么?

I haven't used abstract classes much in practice, though I understand what they are : a way to dictate to subclasses which methods must be implemented.

I just put a Kohana project through Doxygen and can see the class hierarchy in its entirety. I see that, at the top of the chain we have a factory:

abstract class Kohana_Model { 

    public static function factory($name){
        // Add the model prefix
        $class = 'Model_'.$name;
        return new $class;


Inherited directly below that, we have an empty abstract class:

abstract class Model extends Kohana_Model {}

... And below that, there are three inherited classes: Kohana_Model_Database, Kohana_ORM, and Model_Foobar.

Would someone please explain the programming reasoning for this - what is the purpose of having an empty abstract class this high up in the chain? (and, at all?)

Why not have Kohana_Model_Database, Kohana_ORM, and Model_Foobar inherit directly from Kohana_Model, when there is (apparently?) no other branching or inheritance going on between Model and Kohana_Model?

  • 写回答

2条回答 默认 最新

  • dongya6997 2012-02-08 10:43

    Answers you're seeking for are Cascading File System and Transparent Extensions.

    本回答被题主选为最佳回答 , 对您是否有帮助呢?



  • ¥15 delta降尺度计算的一些细节,有偿
  • ¥15 Arduino红外遥控代码有问题
  • ¥15 数值计算离散正交多项式
  • ¥30 数值计算均差系数编程
  • ¥15 redis-full-check比较 两个集群的数据出错
  • ¥15 Matlab编程问题
  • ¥15 训练的多模态特征融合模型准确度很低怎么办
  • ¥15 kylin启动报错log4j类冲突
  • ¥15 超声波模块测距控制点灯,灯的闪烁很不稳定,经过调试发现测的距离偏大
  • ¥15 import arcpy出现importing _arcgisscripting 找不到相关程序