JavaFX-Bugs on GraalVM 19.3 (Java 11)

[Johan Vos]

We have samples showing how to build and run JavaFX applications using
GraalVM. See our blog post [1] with samples [2].

Keep in mind that JavaFX has some characteristics that make it non-trivial
to apply native-image out of the box (reflection/jni configuration,
platform-specific static libraries, including resources and bundles...).
This is why we created Gluon Substrate [3], which does most of this work:
Developers use a maven plugin [4] (gradle will be ready soon too) and this
is used in the samples [2].

If you use GraalVM native-image without all the parameters that Gluon
Substrate adds, you will most likely create a "fallback-image" that still
require a JVM and some other resources to be available at runtime, and this
can give strange results. While I don't exclude JavaFX bugs will surface
using this approach, I think it's more likely you're seeing issues due to
this "mixed mode".

- Johan

[1]
https://gluonhq.com/gluon-substrate-and-graalvm-native-image-with-javafx-support/
[2] https://github.com/gluonhq/client-samples
[3]  https://github.com/gluonhq/substrate
[4] https://github.com/gluonhq/client-maven-plugin

On Wed, Nov 20, 2019 at 10:22 PM Michael Paus <mp at jugs.org> wrote:

> Hi,
>
> I would just like to know where JavaFX problems or bugs should be reported
> which are strictly related to running on the just released GraalVM 19.3
> with
> Java 11 support. Should they go into the regular JBS or should they be
> reported
> elsewhere?
>
> For example: I have observed that a large JavaFX application seems to work
> correctly at first but then suddenly all text on all controls turns
> white and
> white on white or light grey is not really readable anymore. I've never
> observed
> such a behaviour on any other VM before. There is also no error message or
> warning associated with this. It just happens.
>
> There even seem to be more issues when you try to use native-image.
>
> --Michael
>
>