Installing the Java SDK

First and foremost, we will install Java SDK. We will work with Java 8 throughout this book. Go ahead and access this page (http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html). Download the appropriate JDK kit. For Windows/Linux, there are two different versions--one for x86 and another for x64. One should select the appropriate version, and download the appropriate installable file. Once downloaded, double-click on the executable file for Windows, or unTAR and install appropriately for Linux. The instructions for installing Java on Linux can be found on this page (https://docs.oracle.com/javase/8/docs/technotes/guides/install/linux_jdk.html).

The following instructions help one install Java on Windows OS. Double-clicking on the EXE file would start the installer. Once installed, the following needs to be done:

1. Set JAVA_HOME as the path where JDK is installed. 
2. Include the path in %JAVA_HOME%/bin in the environment variable. One can do that by adding the %JAVA_HOME%/bin directory to his/her user PATH environment variable--open up the system properties (Windows key + Pause), select the Advanced tab, and the Environment Variables button, then add or select the PATH variable in the user variables with the value.

Once done with the preceding steps, open a shell and type the command java -version. It should print the version of Java you installed just now.