There are a couple postings on this topic, but I can't get this to work with the latest version of Eclipse. I am using the JRE that comes with 2021-06, the one it puts in p2, x86_64_16.0.2. I have tried various configurations of User Libraries, Maven dependencies, setting PATH_TO_FX, searching Eclipse Marketplace for JavaFX-as-a-plugin, e.g.,
How do I use JavaFX 11 in Eclipse? (2.5 years old)
https://www.javatpoint.com/javafx-with-eclipse
https://www.tutorialspoint.com/javafx-with-eclipse
https://gluonhq.com/products/javafx/
On a couple more elaborate examples, a couple builds had a scattering of missing methods, which I assume is due to JavaFX being somewhat in flux or instructions being quite outdated. I can get a simple Hello, World to build with javafx-sdk-17.0.1 as a User Library (what I'm doing now) and also some of the other configurations. When I try to launch Hello, World with various build-able configurations, I keep getting
Error: JavaFX runtime components are missing, and are required to run this application