Create Gradient Mask in Java

  import java.awt.Color;
import java.awt.GradientPaint;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.geom.Rectangle2D;
import java.awt.image.BufferedImage;
/*from  w  w  w .j  a v a 2 s  . co m*/
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.SwingConstants;

class MyCanvas extends JComponent {
  public void paint(Graphics g) {
    Graphics2D g2d = (Graphics2D)g;

    g2d.drawImage(createGradientMask(200, 200, SwingConstants.HORIZONTAL),10,10,this);

  }  public static BufferedImage createGradientMask(int width, int height, int orientation) {
    // algorithm derived from Romain Guy's blog
    BufferedImage gradient = new BufferedImage(width, height,
            BufferedImage.TYPE_INT_ARGB);
    Graphics2D g = gradient.createGraphics();
    GradientPaint paint = new GradientPaint(0.0f, 0.0f,
            new Color(1.0f, 1.0f, 1.0f, 1.0f),
            orientation == SwingConstants.HORIZONTAL? width : 0.0f, 
            orientation == SwingConstants.VERTICAL? height : 0.0f,
            new Color(1.0f, 1.0f, 1.0f, 0.0f));
    g.setPaint(paint);
    g.fill(new Rectangle2D.Double(0, 0, width, height));

    g.dispose();
    gradient.flush();

    return gradient;
}

}

public class Main {
  public static void main(String[] a) {
    JFrame window = new JFrame();
    window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    window.setBounds(30, 30, 450, 450);
    window.getContentPane().add(new MyCanvas());
    window.setVisible(true);
  }
}


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