private void paintUnderline(Graphics g, int x, int y, int w, int h) {
    g.setColor(tabPane.isEnabled() ? ENABLED_SELECTED_COLOR : DISABLED_SELECTED_COLOR);
    double arc = SELECTION_ARC.get();

    if (arc == 0) {
      g.fillRect(x, y, w, h);
    }
    else {
      RectanglePainter2D.FILL.paint((Graphics2D)g, x, y, w, h, arc, LinePainter2D.StrokeType.INSIDE, 1.0,
                                    RenderingHints.VALUE_ANTIALIAS_ON);
    }
  }
private void paintUnderline(Graphics g, int x, int y, int w, int h)