$ sudo apt-get update
$ sudo apt-get install icedtea-6-jre-cacao 

icedtea-6-jre-cacao is installed in your system.

Make ensure the icedtea-6-jre-cacao package were installed using the commands given below,

$ sudo dpkg-query -l | grep icedtea-6-jre-cacao *

You will get with icedtea-6-jre-cacao package name, version, architecture and description in a table

icedtea-6-jre-cacao package basic information: