[Urgent] using javafx object in java project

Question

Suppose I here created a very simple java project and the main file is like below,
public class test {
    public static void main(String[] args){
            System.out.println("Hello World!");
}and in this particular java project, I need to use another javafx object which is defined as (the javafx and java file are in the same package),
import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.shape.Rectangle;
import javafx.scene.paint.Color;
import javafx.scene.shape.Circle;
var stage: Stage = Stage {
    title: "Declaring Is Easy!"
    scene: Scene {
        width: 300
        height: 250
        content: [
            Circle {
                centerX: 150  centerY: 120 radius: 80
                fill: Color.MAROON
                stroke: Color.INDIANRED
                strokeWidth: 10.0
            }, //Circle
            Rectangle {
                x: 25, y: 80 width: 250, height: 80
                arcWidth: 20 arcHeight: 20
                fill: Color.web("#6699ff")
                stroke: Color.web("#003399")
          strokeWidth: 5.0
            } //Rectangle
        ] //Content
    } //Scene
} //StageSo how could I achieve this?
Regards.

Answer 1

Thanks for your reply.
But would you please elaborate on this sentence: create the fx class using Class.forName("....").newInstance()?
Indeed I implemented an interface which was extended by the javafx class, and in the main java file I need to write following codes to use this object,
Context context = FXLocal.getContext();
        FXClassType instance = context.findClass("packageName.JavaFXClass");
        ObjectValue obj = (ObjectValue)instance.newInstance();
        JavaInterface ji = (JavaInterface)obj.asObject();The problem that I encountered right now is, the exception was thrown at context.findClass("javatest.MyChart");, since it's not able for the compiler to find the JavaFXClass.class.
I checked the folder build\classes\packageName and noticed that both my main JavaClass and JavaInterface have been compiled with .class file, while the JavaFXClass was not, which means the file JavaFXClass.class doesn't exist.
What's the solution?