code: private void paintAd(Graphics2D g) {
          Font oldFont = g.getFont();
          g.setFont(g.getFont().deriveFont(10F));
          g.setColor(axisColor);
          Composite oldComposite = g.getComposite();
          g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.7f));
  
          g.drawString(AD_TEXT,
                  g.getClipBounds().width - g.getFontMetrics().stringWidth(AD_TEXT) - spacing,
                  g.getFontMetrics().getHeight() - spacing + 1);
          g.setComposite(oldComposite);
          g.setFont(oldFont);
      }
docs: Paint the add the same color of the axis but with transparency