Class Constant vs. Class Methods

[Man In Tan]

This isn't really an important question, but since I've been going through my forum, optimizing as much as I can, I thought I might as well ask. I've already gone through and removed all double-quoted strings, almost all redirects, et cetera, so I'm working with the lesser details now.I have several object classes used to store different types of data in a flat file database. I have eleven, actually. Ten of the classes are extended from the eleventh class. Each class has a save_obj() method, to insure that all objects get saved to the correct files. Right now, the save_obj() method uses the static::type constant to determine the directory the file should be saved to. However, since I have to redefine that constant when I extend the class, I was wondering if it might be a good idea to just redefine the method to save to the correct directory, and remove the constant altogether.Obviously both work, but which format would be the better option?

<?php namespace us_0gb;/** * (c) Zero GigaBytes * ..... other documentation here ....**/class catfor {const type = 'catfor';final public function save_obj() {$data = \serialize($this);\file_put_contents(\us_0gb\FFF::$database.'/'.static::type.'/'.$this->_.'.txt', $data);} }class group extends \us_0gb\catfor {const type = 'group';}//And the file continues .....

<?php namespace us_0gb;/** * (c) Zero GigaBytes * ..... other documentation here ....**/class catfor {public function save_obj() {$data = \serialize($this);\file_put_contents(\us_0gb\FFF::$database.'/catfor/'.$this->_.'.txt', $data);} }class group extends \us_0gb\catfor {public function save_obj() {$data = \serialize($this);\file_put_contents(\us_0gb\FFF::$database.'/group/'.$this->_.'.txt', $data);} }//And the file continues .....