In a unix bash script, you can determine the scripts filesystem location by using
SCRIPT_DIR="$( cd "$( dirname "$0" )" && pwd )"
This is especially useful if you want to use “relative” (well, sort of) paths within your script, regardless of which directory the script is being executed from, e.g.
java -jar $SCRIPT_DIR/libs/some-file.jar
If you just used libs/some-file.jar
the bash script would only work when executed from the directory it is located in.