If you are not familiar with the find command, check out our Getting Started article.
The find command may produce many results with the text "Permission Denied."
~]# find / -iname jar find: '/run/user/1000/gvfs': Permission denied . . .
Appending 2>/dev/null will exclude the results that contain Permission Denied from the output.
~]# find / -iname jar 2>/dev/null /opt/bin/jar