[12] RFR: JDK-8209966: Update minimum boot JDK to 11

[Johan Vos]

>
>
> > And it's only going to get worse as time goes on. Would it not be
> > possible to support up until the last JDK LTS(Starting at 11) release
> > for building JavaFX? I feel like maybe that would be more reasonable.
>
> This is a good question, and maybe in the future we might not be so
> quick to do this...or maybe we will.  We should discuss this before we
> get to this point for JavaFX 13, a little less than six months from now.
> The choices for the model are:
>
> 1. Allow building JavaFX N with either JDK N-1 or JDK N.
> 2. Allow building JavaFX N with the most recent LTS or later.
>
> Choice #1 will allow JavaFX to better keep pace with JDK features (API
> or language features). Choice #2 will allow JavaFX to build and run with
> the most current, stable JDK LTS at the cost of not being able to use
> newer JDK features.
>

One of the reasons Java is moving to a fast release cadence is because
today, this is required to stay relevant in a fast-changing landscape.
I think we need to do the same with JavaFX. We should be able to leverage
the latest and greatest advances in the JDK, since this will allow JavaFX
to move fast as well, which is required to stay relevant.

If you want to run on the latest stable JDK LTS, the logical consequence
seems to me you use the latest stable JavaFX LTS. There is LTS support
available for both Java and JavaFX 11 and they are pretty well aligned.

Having said that, there is no point in moving forward just for the fun of
it. We also have to distinguish between changes in the VM or in the core
Java API's.
My opinion is that if a new feature is added to JDK N, we can really take
advantage of it in JavaFX (N+1).
In some cases, there won't be new features relevant to OpenJFX. But even
then, I don't think we can't change our rules on a per-release case (e.g.
JavaFX 14 works with Java 13 and Java 14, and even Java 12; but JavaFX 15
works with Java 14 and Java 15 and not with Java 13).

In general, I think developers updating from JavaFX 11-12-13 are also
capable of updating the JDK from 11-12-13, so I prefer the coupling

1. Allow building JavaFX N with either JDK N-1 or JDK N.

- Johan