There is no documented ability to execute code in JavaFX GUI streams. This is necessary for us to work with JavaFX GUI objects (not created in application's java code) from streams correctly.

There is such an ability in AWT\Swing - the EventQueue.invokeAndWait and EventQueue.invokeLater methods.

Currently, JavaFX GUI is based on AWT\Swing, and we use corresponding sync methods, but such a solution is not optimal.

Firstly, we're not sure that this approach is absolutely correct.

Secondly, currently, JavaFX is based on AWT, but this behavior might be changed by authors in the future.

Thirdly, there are many AWTEventQueue-streams in applets, and there is no strict rule saying which of them can be used for correct synchronisation.

So, we need a universal and documented method that we can use to execute our own Runnable in JavaFX GUI-streams.