Often, I used to encounter a scenario, where I had to switch Java versions on a need basis. I did not know how to do this on Mac OS X(x64).
I had installed Java8 and Java7 on my Mac and had to switch to one of them, once in a while.
/usr/libexec/java_home gives the top Java Version.
/usr/libexec/java_home -V gives the list of JVMs.
You may give the version of interest by using
/usr/libexec/java_home -v 1.7
.bash_profile for Java 7, use the following:
Happy Switching! :)