/usr/share/java/jnlp-jardiff.jar is in libjnlp-servlet-java 20120126-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/java/jnlp-jardiff-20120126.jar
/usr/share/java/jnlp-jardiff-20120126.jar