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Compatibility chart and robot generations
URCaps are generally based on Java 6, since this is required for URCaps to execute on CB3, where only Java 6 is available.
PolyScope on e-Series is using Java 8. URSim are basically the same artifact as PolyScope on the real robot, so they use the same Java version.
The URCaps Starter Package uses OpenJDK 8 to support both URSim generations.