Install oracle java 7 in ubuntu 12.04

Firstly, I don't take credit of this.

I was in need to install java on a new Ubuntu instance in Amazon Web Services.

I found these commands after a long searching and was unaware that Ubuntu needs a  special treatment to install Java.

To install Java you can use following commands:

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

You can check the java version by searching java in dashboard.

Or

If you run:

file /etc/alternatives/java /etc/alternatives/javac

You will get output something like :

/etc/alternatives/java:  symbolic link to `/usr/lib/jvm/java-7-oracle/jre/bin/java'
/etc/alternatives/javac: symbolic link to `/usr/lib/jvm/java-7-oracle/bin/javac'

 Which obviously means you have Java version 7 installed.

This assumes the "alternatives" system is working properly, which might not be the case, depending on how Java has been "messed up" in the past. To check this, run:

file `which java javac`

 Which will show the path where Java is installed.