/usr/share/java/doxia-maven-plugin.jar is in libdoxia-maven-plugin-java 1.1.4-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/java/../maven-repo/org/apache/maven/doxia/doxia-maven-plugin/debian/doxia-maven-plugin-debian.jar