You can also use ubuntu-make
to easily install Eclipse on Ubuntu.
Ubuntu Make is a command line tool which allows you to download the
latest version of popular developer tools on your installation,
installing it longside all the required dependencies (which will only
ask for root access if you don't have all the required dependencies
installed already), enable multi-arch on your system if you are on a
64 bit machine, integrate it with the Unity launcher… Basically, one
command to get your system ready to develop with! - Ubuntu
Wiki
Installing Ubuntu Make :
Ubuntu make is already in official Ubuntu 15.04 repositories, run :
sudo apt-get install ubuntu-make
Installing Eclipse :
umake ide eclipse