Fadeアニメーションで画像を表示

class FadeImage extends JComponent implements ActionListener {
  private int alpha = 10;

  public FadeImage() {
    super();
    setBackground(Color.BLACK);
  }

  @Override protected void paintComponent(Graphics g) {
    Graphics2D g2 = (Graphics2D) g.create();
    g2.setPaint(getBackground());
    g2.fillRect(0, 0, getWidth(), getHeight());
    if (mode && alpha < 10) {
      alpha = alpha + 1;
    } else if (!mode && alpha > 0) {
      alpha = alpha - 1;
    } else {
      animator.stop();
    }
    g2.setComposite(makeAlphaComposite(alpha * .1f));
    g2.drawImage(icon, null, 0, 0);
    g2.dispose();
  }

  @Override public void actionPerformed(ActionEvent e) {
    repaint();
  }

  private AlphaComposite makeAlphaComposite(float alpha) {
    return AlphaComposite.getInstance(AlphaComposite.SRC_OVER, alpha);
  }
}