int w = getWidth();
int h = 70;
GradientPaint gradient = new GradientPaint(0, 0, new Color(255, 255, 255, 255), 2, h, new Color(255, 255, 255, 0), false);
g2.setPaint(gradient);
g2.fillRect(0, 0, w, h);
gradient = new GradientPaint(0, getHeight() - h, new Color(255, 255, 255, 0), 2, getHeight(), new Color(255, 255, 255, 255), false);
g2.setPaint(gradient);
g2.fillRect(0, getHeight() - h, w, h);
}