javafx - Set a shape drawn on another shape as Invisible -

i want draw line passing through circle. however, not want line shown while inside circle. how can accomplish this? note i'm drawing circle first , line.

i used couple of things like:

1. circle.setopacity 1, didn't help!
2. used line.toback() after adding circle , line in same group. didnt either

line.toback()

line.tofront()

import javafx.application.application; import javafx.geometry.insets; import javafx.scene.scene; import javafx.scene.control.button; import javafx.scene.layout.*; import javafx.scene.paint.color; import javafx.scene.shape.*; import javafx.stage.stage;  public class lineundercircle extends application {         @override     public void start(stage stage) throws exception {         line line = new line(10, 10, 50, 50);         line.setstrokewidth(3);          circle left  = new circle(10, 10, 8, color.forestgreen);         circle right = new circle(50, 50, 8, color.firebrick);          button linetoback = new button("line back");         linetoback.setonaction(e -> line.toback());         button linetofront = new button("line front");         linetofront.setonaction(e -> line.tofront());          pane shapepane = new pane(line, left, right);          hbox controlpane = new hbox(10, linetoback, linetofront);          vbox layout = new vbox( 10, controlpane, shapepane);         layout.setpadding(new insets(10));          stage.setscene(new scene(layout));         stage.show();     }      public static void main(string[] args) {         launch(args);     } }