$ sudo apt-get update
$ sudo apt-get install libjets3t-java 

libjets3t-java is installed in your system.

Make ensure the libjets3t-java package were installed using the commands given below,

$ sudo dpkg-query -l | grep libjets3t-java *

You will get with libjets3t-java package name, version, architecture and description in a table

libjets3t-java package basic information: