How to install jdk on Ubuntu
##Install JDK
sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
sudo apt-get install oracle-java7-installer
##Install Gradle
sudo add-apt-repository ppa:cwchien/gradle
sudo apt-get update
Install specified version
sudo apt-get install gradle-2.2
Install latest version
sudo apt-get install gradle-ppa