jEnv is a command line tool to help you forget how to set the JAVA_HOME environment variable. jenv is for a equivalent of rbenv, but for Java environment. It allow to easily switch between several JDKs installations (already presents), and configure which one to use per project. http://www.jenv.be/ https://github.com/gcuisinier/jenv http://davidcai.github.io/blog/posts/install-multiple-jdk-on-mac/