at java.net.PlainSocketImpl.socketBind(Native Method)
The error doesn't tell me the port number that is in used so I tried to search and found out that the port being used by the java instance above (or whatever it is called) is 8093. I found it in uil2-service.xml:
The port above is not being used by any service after I shutdown JBoss (I can check it by using lsof or netstat). I also make sure that after the shutdown, there is no service left running including java instances.