How to kill all specific java processes - linux

Question

I have following search result coming from netstat:
netstat -nap | grep java | grep :::300*
(Not all processes could be identified, non-owned process info
will not be shown, you would have to be root to see it all.)
tcp6 0 0 :::30008 :::* LISTEN 81159/java
tcp6 0 0 :::30010 :::* LISTEN 81164/java
tcp6 0 0 :::30001 :::* LISTEN 81155/java
tcp6 0 0 :::30002 :::* LISTEN 81162/java
tcp6 0 0 :::30003 :::* LISTEN 81156/java
tcp6 0 0 :::30004 :::* LISTEN 81161/java
tcp6 0 0 :::30005 :::* LISTEN 81158/java
tcp6 0 0 :::30006 :::* LISTEN 81157/java
tcp6 0 0 :::30007 :::* LISTEN 81160/java
now I need to iterate over that result, get the process id ad kill it. How can I do it ?

Answer 1

PIDS=( $(netstat -nap | grep java | grep :::300*| awk '{print $6}' | cut -d/ -f2 | xargs) ); for p in "${PIDS[#]}"; do kill -9 ${p}; done
i think you can do like this but i think can be more easy way

Answer 2

It's not good code, but the following does what you asked for (newlines added for clarity, would be equally correct without them):
kill $(netstat -nap | awk '
/java/ && /:::300[[:digit:]]{2}/ {
gsub(/\/.*$/, "", $6);
gsub(/[^[:digit:]], "", $6);
print $6
}
')
The second gsub is a safety measure, to ensure that only digits are printed; this reduces the chances of shell globbing or string splitting having unintended effects should the column ordering be off.
Consider using systemd or another process supervision framework to manage services, instead of doing this kind of thing with hand-written code.