Ubuntu/Applications/Java7

Install Applications | Java7
http://askubuntu.com/questions/56104/how-can-i-install-sun-oracles-proprietary-java-6-7-jre-or-jdk
https://help.ubuntu.com/community/Java

Download Java:

http://download.oracle.com/otn-pub/java/jdk/7u13-b20/jre-7u13-linux-i586.tar.gz

Remove OpenJDK:

sudo apt-get purge openjdk*

Extract downloaded tar:

tar -xvf ~/Downloads/jre-7u13-linux-i586.tar.gz

Move Java to common location:

sudo mv jre1.7.0_13/* /usr/lib/jvm/jre1.7.0/

Determine current installed java alternatives:

sudo update-alternatives --config java

There are 2 choices for the alternative java (providing /usr/bin/java).

Selection Path Priority Status
————————————————————
* 0 /usr/lib/jvm/java-6-openjdk/jre/bin/java 1061 auto mode
1 /usr/lib/jvm/java-6-openjdk/jre/bin/java 1061 manual mode
2 /usr/lib/jvm/java-6-sun/jre/bin/java 63 manual mode

Press enter to keep the current choice[*], or type selection number:

The above example shows you have (3) variants, 0-2. You'll want to install the next as (3).
Update Alternatives with Java 7

sudo update-alternatives --install /usr/bin/java /java /usr/lib/jvm/jre1.7.0/bin/java 3

Configure Java:

sudo update-alternatives --config java

select the one that has Java 7 via the number to the far left.

Check Installed Version:

java -version