how big of a technical leap is it to from Java UI dev (Swing/Java2D/JavaFX) to Android? I know Chet Haase and Romain Guy did so curious to know if it is an easy

how big of a technical leap is it to from Java UI dev (Swing/Java2D/JavaFX) to Android? I know Chet Haase and Romain Guy did so curious to know if it is an easy transition.