Mac how to kill the process?

First we should know the port is being used?

Mac :

you can input 

netstat -anp tcp | grep 8080
you will get some info


If you Mac system is "EI Caption"
you should input 
lsof -i tcp:8080


How to look process pid number?
int the bash input :

ps -au | group name

you can see this link:
http://www.chriswrites.com/how-to-view-and-kill-processes-using-the-terminal-in-mac-os-x/