Set default JDK on Mac OS X

To set to JDK 6

export JAVA_HOME=$(/usr/libexec/java_home -v 1.6)

To set JDK 7

 export JAVA_HOME=$(/usr/libexec/java_home -v 1.7)

To set JDK 8

 export JAVA_HOME=$(/usr/libexec/java_home -v 1.8) 

Source: 

https://coderwall.com/p/esa4sg 

http://www.jayway.com/2014/01/15/how-to-switch-jdk-version-on-mac-os-x-maverick/