How to use

setStroke

method

in

javafx.scene.shape.Arc

final Paint initialColor = arc.getStroke();
if (initialColor == null) {
  arc.setStroke(blueColor);

private static Arc createArc(Color stroke, double strokeWidth) {
  Arc a = new Arc();
  a.setStartAngle(135);
  a.setLength(-270);
  a.setFill(Color.TRANSPARENT);
  a.setStroke(stroke);
  a.setStrokeWidth(strokeWidth);
  return a;
}

public GeneratorSymbol(Color stroke, double strokeWidth, double size) {
  setPrefSize(size, size);
  c = new Circle();
  c.setFill(Color.TRANSPARENT);
  c.setStroke(stroke);
  c.setStrokeWidth(strokeWidth);
  a1 = new Arc();
  a1.setStartAngle(0);
  a1.setLength(180);
  a1.setFill(Color.TRANSPARENT);
  a1.setStroke(stroke);
  a1.setStrokeWidth(strokeWidth);
  a2 = new Arc();
  a2.setStartAngle(0);
  a2.setLength(-180);
  a2.setFill(Color.TRANSPARENT);
  a2.setStroke(stroke);
  a2.setStrokeWidth(strokeWidth);
  getChildren().addAll(c, a1, a2);
}

final Paint initialColor = arc.getStroke();
if (initialColor == null) {
  arc.setStroke(blueColor);