Changing current version of Java within Windows

In the command shell:

set JAVA_HOME=C:\jdk1.6.0u24
set PATH=%JAVA_HOME%\bin;%PATH%

That will temporarily set up the environment in the command shell. Maven, Ant, etc. will pick up on your new version of Java without having to go to the Control Panel repeatedly.
Tools like Eclipse should be able to select which JDK to use in their own configuration tools for use within their environments.

http://superuser.com/questions/262757/changing-current-version-of-java-within-windows