/usr/share/binfmts/jarwrapper is in jarwrapper 0.63ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 | package jarwrapper
detector /usr/bin/jardetector
interpreter /usr/bin/jarwrapper
magic PK\x03\x04
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