[CentOS] netstat - kill by pid ?

I am writing a small script to kill process(es) listening on particular port number. Here I am particularly looking at Java servlet-containers like Tomcat and JBoss, which sometimes don't complete their shutdown process and it still shows up as running process with ps or netstat. This needs to be kill-ed and for that knowing pid of that process is necessary. The netstat by default doesn't give only pid(s), so one has to use sed/awk/tr like utility to extract pid info. Does anyone know any program/utility which gives pid(s) based on listening port numbers? Or is there any option in netstat that I am missing?

Thanks, CS.