Installing Java

Mac

• Checking if your Mac already has a version installed can be done by entering the following command in the terminal:

   java -version 

  If it was already installed you will get a version number and you can stop here.
  Otherwise, the command will not have been found meaning there is Java installed yet. In that case, follow the next steps.
• Installing Homebrew (a very useful package manager):

   /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)" 

• Installing Java:

    brew cask install java 

• You are all set (you can update Java anytime by running brew update).

Linux

• Open up the commandline and update the package index by running:

   sudo apt-get update 

• Next, check if you have Java installed:

   java -version 

  If you see a " not found " message, follow the next steps.
• To install Java run:
  sudo apt-get install default-jre (Java Runtime Environment)
  sudo apt-get install default-jdk (Java Development Kit)
• You are done.

Windows

• Contrary to the other two platforms, installing Java on windows is actually easier to do without the commandline.
• Download the installer here and run it.