/usr/share/maven-repo/org/jruby/ext/posix/jnr-posix/debian/jnr-posix-debian.jar is in libjnr-posix-java 1.1.8-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/maven-repo/org/jruby/ext/posix/jnr-posix/debian/../../../../../../../java/jnr-posix-1.1.8.jar