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Invoke Tools->Java Platforms

Import the NetBeans Projects
Open Project... (you may need to resolve missing junit jars, don't open web or builders for now)
Rebuild
This might take quite a long time depending on how fast your machine it. There should be no red marks on any of the projects.
Run Sample Code
Here is some sample code that was hooked up to use the base, graphics and controls projects. When saved, these projects were built by the IDE and the same code executed using the source in the IDE.
Run Sample Code with gradle built shared libraries
//TODO - explain how to hook up the shared libraries in the run dialog
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