I installed an application that required port 8080. I was unable to execute the application as port 8080 was already in use. Unable to determine which application, I changed the setting for the application I had just installed to port 8090. Success. However, I still wanted to know if anything was running on port 8080. Like Windows, Linux has a command line utility, netstat. Their capabilities and outputs are slightly different, however, in either case, you should be able to understand the results. There are many options and commands, but I found from within a forum , the command line that gave me the results I was looking for.
The command to use:
netstat -anp | grep 8000
To find out more about the switches that netstat and grep use, type --help at the end of the command line. (ie netstat --help or grep --help). The commands used in this example are the following:
-a, --all, --listening display all sockets (default: connected)
-n, --numeric don't resolve names
-p, --programs display PID/Program name for sockets
grep to search for PATTERN in each FILE or standard input.