Override a class like Dispatcher

[be_tnt]

Hello,

 

I was about to override the Dispatcher class (prestashop 1.5.3.1) but I have notice that the override folder already contains all the classes. Some files only contain the class definition but some (at least one) - the Dispatcher class - contains the createUrl method. Is that normal?

 

Does it mean that all those files will be overwritten during an upgrade?

 

Thx!