How to quickly kill java processes in bash?

Question

On a linux box, I have at most 3 java jars files running. How do I quickly kill all 3 with one command?

Usually I would:

ps ex - get the processes running

then find the process ids then do:

kill -9 #### #### ####

Any way to shorten this process? My eyes hurts from squinting to find the process ids.

My script does the following:

nohup ./start-gossip &

nohup ./start &

nohup ./start-admin &

Is there a way to get the process ids of each without looking it up?

Answer 1

Short answer:

pkill java

This looks up a process (or processes) to kill by name. This will find any other java processes too, so be careful. It also accepts -9, but you should avoid using -9 unless something is really broken.

EDIT:

Based on updates, you may be able to specify the script names to pkill as well (I'm not positive). But, the more traditional way to handle this issue is to leave pid files around. After you start a new process and background it, its pid is available in $!. If you write that pid to a file, then it's easy to check if the process is still running and kill just the processes you mean to. There is some chance that the pid will be reused, however.

Answer 2

You can save the PIDs when you start the processes so you can use them later:

nohup ./start-gossip &
START_GOSSIP_PID=$!

nohup ./start &
START_PID=$!

nohup ./start-admin &
START_ADMIN_PID=$!

...

kill -9 $START_GOSSIP_PID
kill -9 $START_PID
kill -9 $START_ADMIN_PID

This has the advantage (over pkill) of not killing off any other processes that coincidentally have similar names. If you don't want to perform the kill operation from the script itself, but just want to have the PIDs handy, write them to a file (from the script):

echo $START_GOSSIP_PID > /some/path/start_gossip.pid

Or even just do this when you launch the process, rather than saving the PID to a variable:

nohup ./start-gossip &
echo $! > /some/path/start_gossip.pid