/usr/share/java/swt.jar is in libswt-gtk-3-java 3.8.2-5.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/java/../../lib/java/swt-gtk-3.8.2.jar
/usr/share/java/../../lib/java/swt-gtk-3.8.2.jar