Chat Cooldown Plugin (AsyncPlayerChatEvent event)

Hi,

I need some help with a plugin that I creating. So, the basic line is that every time a player time's something into chat, he has to wait a certain amount of seconds ( Which I know how to do ), though I don't know how make the actual Cooldown itself from where the player type's something into chat.
If you have any suggestions or link's that will be helpful, feel free to post them below.

 

Code:

List<String> cooling = new ArrayList<String>();
 
@EventHandler
public void onChat(AsyncPlayerChatEvent e) {
    // TODO: event checks
 
    String name = e.getPlayer().getDisplayName();
 
    // Cancel event if player is cooling down
    if(cooling.contains(name) {
        e.getPlayer().sendMessage("Thou shall not speak!");
        e.setCancelled(true);
    } else {
        cooling.add(name);
        // TODO: add timer that removes player from list after x amount of seconds
    } 
}

 

Make sure that you make it thread safe!