The JavaFX installation contains a demo application named Charts Sampler which is a good example of what JavaFX might be used for. But in practice JavaFX would be completely useless for building such an application because typically you would not only want to see some nice charts on the screen but you would also like to print them or render them into an image in order to create a report with them. To my knowledge JavaFX currently does not support printing of scenes or rendering them into an image so its practical use is drastically limited. The minimum requirement is support for rendering into an image which you could also use for printing. Of course there also must be official support to store such an image to a file and to convert it into an old BufferdImage. I know of the to/fromExternalImage methods but I am not sure whether they are official because they are flagged as implementation dependent and are currently not documented.

In addition it would also be nice to be able to render into some vector based file, but that is not so important.