Ubuntu has dropped including Sun/Oracle Java in its repository, and added OpenJDK. But, the former is more reliable than latter, and is also must for some applications.  Here is a way to add Sun java 6:   sudo add-apt-repository ppa:webupd8team/java  sudo apt-get update  sudo apt-get install oracle-java6-installer  Possible error : "couldn't connect to host"   To make this version as default: here .   If you want to install java 7, instead of last command try   sudo apt-get install oracle-java7-installer  If you are under proxy network or seen a error like   Cannot add PPA: 'ppa:webupd8team/java'. Please check that the PPA name or format is correct.  and if you are sure that the PPA is working, the try   sudo -E add-apt-repository ppa:webupd8team/java  and proceed with remaining commands.