/usr/share/java/groboutils-thread-core.jar is in libgroboutils-java 5-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/java/groboutils-thread-1.0.0alpha2-core.jar
/usr/share/java/groboutils-thread-1.0.0alpha2-core.jar