testPI4J is a library to allow you to run your PI4J projects on your computer: develop, debug and run on your computer. When you are done, you have only to replace the testPI4J library for the real PI4J library and that's it: you can run your java program on the Raspberry Pi wihtout recompiling
ProviewPi is a SD image with an unofficial Proview release for the Raspberry Pi.
ProviewPi is obsolete.
There has become an official Raspbian Proview V5.0 release.
You can get it here:
https://sourceforge.net/projects/proview/files/proview/proview_5.0.0-1/raspbian/
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