Classes indise lib folder not refreshed until reboot server

Hello,

I just test to use the lib folder. I add simple test class with a
function that return the argument.upcase. And this is working good.
But if I change to argument.downcase, I always have upcase. Even if I
quit the browser and return to the page.

I must restart the server to see change. There is another solution. More
easy ?

So, if the site is online, on Textdrive. How apply change ? Need to
restart, and how ?

Thanks