Prevent php class extension

Question

for a while I try to decode my own shared file that contain all the important functions in the class but I think when I have a class like

class A { public function test($value){ 

and file encoded

maybe someone that

 class B extends A { public function test($value){ 

and change the whole function that contains my code that I can discover for myself.

http://www.php.net/manual/en/language.oop5.php

Answer 1

Use final .

Answer 2

 final class A { public function test($value){ 

or

 class A { final public function test($value){ 

Answer 3

Use final keyword