Today, I try to develop my apps with ADT on Ubuntu 14.04
The problem is jdk is not installed, and the second I can not read file by extension RAR.
The solution is
1. Open terminal, unsure that connect internet and type some command below.
sudo apt-get install openjdk-7-jre
We need to install either the openjdk-7-jre or oracle-java7-jre package.
2. About RAR problem I get solution , we open the terminal, and type this command
apt-get install unrar
To extract the file RAR we just type
unrar x myrararchive.rar