Question

Is it possible to change the application icon using JavaFX, or does it have to be done using Swing?

Answer 1

Assuming your stage is “stage” and the file is on the filesystem:

stage.getIcons().add(new Image("file:icon.png"));

As per the comment below, if it’s wrapped in a containing jar you’ll need to use the following approach instead:

stage.getIcons().add(new Image(<yourclassname>.class.getResourceAsStream("icon.png")));