Sometimes, we need to use a selected Java virtual machine, and rarely is the Ubuntu's preinstalled, gij, but the official from Sun. To solve it should be as easy as installing the appropiated .deb packages, but it won't work, we install them and still get gij instead of Sun's.

To get to use the JVM from Sun we'll have to run the next command, forgotten for some reason by the java package maintainers:

sudo update-alternatives --config java

We'll be offered the different installed JVM and then, just have to choose our favourite.