Java Graphics2D用透明颜色绘制图像

Question

I want to know as simple as possible solution (so far I found only very complex solution) to simple question : How to draw an image in Graphics2D and set one color as fully transparent?

So far, I was trying something like this, but with no success :

private Image head;
public void draw(Graphics2D g) {      
    g.setComposite(AlphaComposite.Src);
    Color transparentWhite = new Color(255,255,255,1);
    g.drawImage(head, (int)posX, (int)posY, transparentWhite, null);        
}

I have picture with white color around it which I do not want to draw.

Answer 1

Ok, finally found an answer, this is the most easies solution I have found.

private Image head;

//This is constructor, here I use method that adding transparency to image.
public Character(BufferedImage head){
        this.head = makeColorTransparent(head, Color.WHITE);
}

public void draw(Graphics2D g) {
        g.drawImage(head, (int) posX, (int) posY, null); //variable head is saved with transparency, so now it is drawing right
}

//Just copy-paste this method
public static Image makeColorTransparent(BufferedImage im, final Color color) {
    ImageFilter filter = new RGBImageFilter() {

        // the color we are looking for... Alpha bits are set to opaque
        public int markerRGB = color.getRGB() | 0xFF000000;

        public final int filterRGB(int x, int y, int rgb) {
            if ((rgb | 0xFF000000) == markerRGB) {
                // Mark the alpha bits as zero - transparent
                return 0x00FFFFFF & rgb;
            } else {
                // nothing to do
                return rgb;
            }
        }
    };

    ImageProducer ip = new FilteredImageSource(im.getSource(), filter);
    return Toolkit.getDefaultToolkit().createImage(ip);
}