First, make sure that your OSX is virgin from JRE. Check it out from your favorite browser (Safari or Firefox) by loading an applet sample page (eg: from this link). If your browser displaying an unsupported plugin just like picture below, then it's the sign that your OSX still not Java ready yet.
If you guess that it may resolve from auto-search plugin window (for example from Firefox browser), then certainly that Firefox couldn't find it best suitable.
If you guess that it may resolve from Sun website, then you may find an answer that the JRE's only available from Software Update feature.
If you guess that Software Update feature will find you this lost JRE, then you probably find nothing up there.
So, where the hell is this JRE package? In a middle of annoyed situation, a knowledge base website from Apple has an important update information regarding to this case (http://support.apple.com/kb/DL848).
Finally, the patch package has founded. Download it & make an install like usual package. Note that you need to close your active browser before running the patch!
After the installation completed, try to open browser & execute your applet sample.
Like image above, so the case is closed now :)
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