Color oldColor = g2D.getColor();
// Fill left and right border with a gradient
for (int i = 0; i < 5; i++) {
g2D.setColor(new Color(128, 128, 128, 200 - i * 45));
g2D.drawLine(x + width - 5 + i, y + i, x + width - 5 + i, y + height - 5 + i);
g2D.drawLine(x + i, y + height - 5 + i, x + width - 5 + i - 1, y + height - 5 + i);
}
g2D.setColor(oldColor);
}
},
BorderFactory.createLineBorder(Color.BLACK)));