An application server may already be running on localhost issue resolved!!

SOLUTION

1) open cmd

2) type netstat -noa 

    you will get list of ipaddress and their ports then you can select an ipaddress which uses port 8080 which is 0.0.0.0:8080 in my case and get its PID which is 2560 in my case

3) type taskkill /PID 2560 /F

you can now start the server and check.