this script checks if a (global) version was set by jenv. if so, use that path if no version was requested explicitly (e.g. by java_home -v '1.7.*' or something)
# set env if not already done so. something like this for bash
echo "export JAVA_HOME=`/usr/libexec/java_home`" >> ~/.bash_profile;
# this should be brew install something, but for now...