This test, java/awt/Mouse/EnterExitEvents/ModalDialogEnterExitEventsTest.java, fails for me with jdk9 PIT for b137 (where it is introduced) on Linux with NPE apparently not having openButton assigned yet by the moment of Util.clickOnComp(openButton, robot, 500);

The same test runs on the original target platform, OS X 10.11, some 45 seconds or more, running rainbow wheel.

There's some synchronization issues I guess.