Update JavaFX GUI Periodically (e.g. every second)

If you want to periodically display new data in your GUI, then you could use "Timeline" (all classes from the javafx.*-packages), e.g. for updating every 1.0 second:

Timeline timeline = new Timeline(
    new KeyFrame(Duration.seconds(1.0), e -> {
        /*
         * read new data and update GUI nodes here ...
         */
    })
);
timeline.setCycleCount(Timeline.INDEFINITE);
timeline.play();

If you use FXML, a good point to call this piece of code would be in your FXML controller class:

public class ControllerForFXML implements Initializable {

    @Override
    void initialize(URL location, ResourceBundle resources) {
        /*
         * Timeline code from above here ...
         */
    }
}