Open terminal and do the following:

[korey@localhost ~]$ cd /Library/Java/JavaVirtualMachines
[korey@localhost /Library/Java/JavaVirtualMachines]$ ls -al

This will give you a list of JDKs that you have installed. To set the default java version to 1.8.0_131 for example, use the following command:

[korey@localhost ~]$ /usr/libexec/java_home -v 1.8.0_131 --exec javac -version

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