Installing Java 7 on Ubuntu

Question

to install java I have always used the classic way from the terminal. I would like to install java manually. I placed the folder of the JDK on the desk and I set environment

Answer 1

sudo apt-get update
sudo apt-get install openjdk-7-jdk

and if you already have other JDK versions installed

sudo update-alternatives --config java

then select the Java 7 version.