This week's book giveaway is in the Mac OS forum. We're giving away four copies of a choice of "Take Control of Upgrading to Yosemite" or "Take Control of Automating Your Mac" and have Joe Kissell on-line! See this thread for details.
Most likely you just need to set your PATH to include Java's bin directory. There are instructions for setting paths on various OSes here: http://java.com/en/download/help/path.xml It says that it shouldn't be necessary for Windows, but I'm not sure why. It might mean the installer was supposed to do it, or maybe it's only talking about java (the runtime), not javac (the compiler). In any case, my recommendation is to set an environment variable called JAVA_HOME to the root folder of your installation, and then add %JAVA_HOME%\bin to your PATH environment variable.