How to install Eclipse 4.3 Kepler or Eclipse 4.2 Juno and pre-requisite Oracle Java 7 on Ubuntu 13.04 Raring / Ubuntu 12.04 Precise LTS / Linux Mint 15 Olivia (the recommended method)

Eclipse is one of the most widely used free and open-source IDEs out there in the professional Software Development industry.
Still, both Ubuntu 13.04 Raring (as well as the LST Ubuntu 12.04.x) and Linux Mint 15 Olivia has a seemingly very old version of Eclipse in their repositories.
Here is a how-to on installing the latest and greatest version of Eclipse 4.3 Kepler (this whould also work for Eclipse 4.2 Juno) on Ubuntu 13.04 Raring / Ubuntu 12.04 Precise / Linux Mint 15 Olivia:

First of all, we have to install Oracle Java 7.
Both Ubuntu and Linux Mint have OpenJDK in their repositories, but that won't work for Eclipse.

To install Oracle Java 7, use the following commands in Terminal:

sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
sudo apt-get install oracle-java7-installer

As the installation progresses, you might be asked to accept the Oracle licence/terms.
Use the arrow keys to move between the options, and press ENTER to select the option (Choose Yes/Accept/OK/Continue) and continue with the installation.

Once Oracle Java 7 has been installed,
to set the required Oracle Java 7 environment variables, run the following command:

sudo apt-get install oracle-java7-set-default

Now, download the latest (or the required) version of Eclipse from
eclipse.org/downloads/

Extract and click on the file named 'eclipse' - it should now run fine without any issue. :-)

Happy Coding!!!