form pahimars github
Download and install the Java JDK.
Windows/Mac download link. Scroll down, accept the Oracle Binary Code License Agreement for Java SE, and download it (if you have a 64-bit OS, please download the 64-bit version).
Linux: Installation methods for certain popular flavors of Linux are listed below. If your distribution is not listed, follow the instructions specific to your package manager or install it manually here.
Gentoo: emerge dev-java/oracle-jdk-bin
Archlinux: pacman -S jdk7-openjdk
Ubuntu/Debian: apt-get install openjdk-7-jdk
Fedora: yum install java-1.7.0-openjdk
Windows: Set environment variables for the JDK.
Go to Control Panel\System and Security\System, and click on Advanced System Settings on the left-hand side.
Click on Environment Variables.
Under System Variables, click New.
For Variable Name, input JAVA_HOME.
For Variable Value, input something similar to C:\Program Files\Java\jdk1.7.0_51 exactly as shown (or wherever your Java JDK installation is), and click Ok.
Scroll down to a variable named Path, and double-click on it.
Append ;%JAVA_HOME%\bin EXACTLY AS SHOWN and click Ok. Make sure the location is correct; double-check just to make sure.
Open up your command line and run javac. If it spews out a bunch of possible options and the usage, then you're good to go. If not, either try the steps again or check the FAQ.