I have installed Android Studio and I followed all steps described here
But when I start studio.sh I got an error with this message:
On ubuntu I have tried all the methods that are described here but none worked.
What I did in the end was to:
download JDK from oracle, extract the archive
edit android-studio/bin/studio.sh and add at the top
export JAVA_HOME=/path/to/jdk
save the file and cd android-studio/bin and launch Android Studio: ./studio.sh