I'll add that internal classes, mostly NG___ peers, can also benefit from sealing. NGLightBase is an example.
Material is another public class that can be sealed. On Wed, Feb 1, 2023 at 7:37 PM Kevin Rushforth <kevin.rushfo...@oracle.com> wrote: > I agree that we should only seal existing classes that could not have been > extended by application classes. The ones I listed in my previous email fit > that bill, since an attempt to subclass them will throw an exception when > it is used in a scene graph. Each documents that subclassing is disallowed. > > Btw, we've already started making use of pattern-matching instanceof in > the implementation anyway. It would be the first API change that relies on > a JDK 17 feature, but for JavaFX 21, I see no problem in doing that. > > -- Kevin > > > On 2/1/2023 9:06 AM, Philip Race wrote: > > In the JDK we've only sealed existing classes which provably could not > have been extended by application classes, > so I'm not sure about this .. > > also I think that might be the first change that absolutely means FX 21 > can only be built with JDK 17 and later .. > > -phil > > On 2/1/23 8:59 AM, Thiago Milczarek Sayão wrote: > > Yes, sorry, I made the email title in plural, but I meant what Michael > said, Node would be sealed permitting only what is needed for JavaFx > internally. > > > -- Thiago > > > Em qua., 1 de fev. de 2023 às 13:48, Michael Strauß < > michaelstr...@gmail.com> escreveu: > >> I don't think that's what Thiago is proposing. Only `Node` would be >> sealed. >> The following subclasses would be non-sealed: Parent, SubScene, >> Camera, LightBase, Shape, Shape3D, Canvas, ImageView. >> And then there are additional subclasses, which don't fit into this >> idea since they are in other modules: SwingNode (in javafx.swing), >> MediaView (in javafx.media), Printable (in javafx.web). >> >> >> >> On Wed, Feb 1, 2023 at 5:39 PM John Hendrikx <john.hendr...@gmail.com> >> wrote: >> > >> > I think this may be a bit unclear from this post, but you're proposing >> I think to make `Node`, `Shape` and `Shape3D` sealed. For those unaware, >> you're not allowed to extend these classes (despite being public). For >> example Node says in its documentation: >> > >> > * An application should not extend the Node class directly. Doing so >> may lead to >> > * an UnsupportedOperationException being thrown. >> > >> > Currently this is enforced at runtime in NodeHelper. >> > >> > --John >> > >> > On 01/02/2023 15:47, Thiago Milczarek Sayão wrote: >> > >> > Hi, >> > >> > NodeHelper.java has this: >> > >> > throw new UnsupportedOperationException( >> > "Applications should not extend the " >> > + nodeType + " class directly."); >> > >> > >> > I think it's replaceable with selead classes. Am I right? >> > >> > The benefit will be compile time error instead of runtime. >> > >> > >> > -- Thiago. >> > >> > > >
