1-Of course not, the JVM depends on what the user has installed, probably when leaving the 9 should be able to run also 8, so the JVM will be no problem there will be guaranteed to be able to run programs from previous versions.
2-Probably however I believe there will be external libraries for Swing / AWT, it will not be official but it should work the same way with no improvement.
3-JavaFX overcomes in many points Swing, javaFX has a much simpler API besides being more customizable with css but the swing is not much behind but as at this moment javaFX is has great improvements does not make sense to continue with the "worst."