Comment créer un script d'init pour une application java.

EDIT : ce truc n'a pas marché pour moi :
s=ps -C 'java -jar /path/to/application.jar' -o pid h
Du coup, j'ai remplacé par :
s=$(pgrep --full 'une string unique qui identifie la command line pour lancer mon jar')

!/bin/sh

#

init script for a Java application

#

Check the application status

#

This function checks if the application is running

check_status() {

Running ps with some arguments to check if the PID exists

-C : specifies the command name

-o : determines how columns must be displayed

h : hides the data header

s=ps -C 'java -jar /path/to/application.jar' -o pid h

If somethig was returned by the ps command, this function returns the PID

if [ $s ] ; then
return $s
fi

In any another case, return 0

return 0

}

Starts the application

start() {

At first checks if the application is already started calling the check_status

function

check_status

$? is a special variable that hold the "exit status of the most recently executed

foreground pipeline"

pid=$?

if [ $pid -ne 0 ] ; then
echo "The application is already started"
exit 1
fi

If the application isn't running, starts it

echo -n "Starting application: "

Redirects default and error output to a log file

java -jar /path/to/application.jar >> /path/to/logfile 2>&1 &
echo "OK"
}

Stops the application

stop() {

Like as the start function, checks the application status

check_status

pid=$?

if [ $pid -eq 0 ] ; then
echo "Application is already stopped"
exit 1
fi

Kills the application process

echo -n "Stopping application: "
kill -9 $pid &
echo "OK"
}

Show the application status

status() {

The check_status function, again...

check_status

If the PID was returned means the application is running

if [ $? -ne 0 ] ; then
echo "Application is started"
else
echo "Application is stopped"
fi

}

Main logic, a simple case to call functions

case "$1" in
start)
start
;;
stop)
stop
;;
status)
status
;;
restart|reload)
stop
start
;;
*)
echo "Usage: $0 {start|stop|restart|reload|status}"
exit 1
esac

exit 0