Plugin Level

seeing you placed this in development, I'll give you some pseudo code.
asynch player chat event
get the prefix of the event
string prefix = player.getLevel() + " " + receivedprefix // maybe some chat formatting as well? thisll just be a nr in front of his name and shit
set the prefix of the event
done.

 

http://gyazo.com/60fc1c149f2a17e93b3c37cccdce3afb
Since you posted here I assume you want to create your own plugin or integrate it in your own plugin...

 

!!!!!!

 

This was posted in "Spigot Plugin Development". Here you get help with developing plugins in Spigot.

 

This means @sinxao posted it at the wrong section!!!

 

You can use my plugin recently added a ranking system.

http://www.spigotmc.org/resources/stats-pvp.6458/

 

@sinxao I can do this for you. PM me.