void (@NotNull Graphics g) { Graphics2D g2d = (Graphics2D)g.create(); g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); g2d.setColor(getBackground()); g2d.fillRoundRect(0, 0, getWidth(), getHeight(), getHeight() - 2, getHeight() - 2); g2d.setColor(getBackground().darker()); g2d.drawRoundRect(0, 0, getWidth() - 1, getHeight() - 1, getHeight() - 2, getHeight() - 2); g2d.dispose(); }