How to check which port is in use by Oracle ?

so ... step by step solution ....

• login to sql as admin* 
• type: SELECT dbms_xdb.gethttpport FROM dual;
• (you will see which port is used)

(To check is server is running For windows:
run command line (cmd) and type:
netstat -na | findstr :8080 -- to check is server is running

INFO: 8080 or port number displayed as result of 

SELECT dbms_xdb.gethttpport FROM dual;

* 2 ways
1)
from command line
type: sqlplus / as sysdba
type your password

2)
from oracle's command line
(C:\oraclexe\app\oracle\product\11.2.0\server\bin\sqlplus.exe /nolog
type: connect
type: system
type: your password

C:\oraclexe\app\oracle\product\11.2.0  this can vary depends on your instalation path and version of oracle