The files in
/usr/lib/jni were all installed by various Ubuntu packages and they can be restored by reinstalling those packages. You can reinstall a package with a command like:
sudo apt-get install --reinstall <packagename>
<packagename> is the name of the package you want to reinstall.
Figuring out which packages you need to reinstall might be a little tricky, because it looks like multiple packages install files in
/usr/lib/jni. You can probably get a rough idea of the packages to reinstall with this command:
dpkg -l | grep jni
That will list the packages you have installed with
jni in their names. I would start by reinstalling each of those packages and see if it fixes your problem.