Graphics object with transparent background

Question

Ive been trying to create an image using a graphics object, which i want to have a transparent background. I have been researching on the net and have come up with something like this, but its not really getting the job done. Im still getting an image with a black background. The image will always be 200 by 100 pixels.
public void drawGraph(Graphics2D g,int a,int b, int d)
         Composite oldComp = g.getComposite();
         Composite alphaComp = AlphaComposite.getInstance( AlphaComposite.CLEAR);
         g.setComposite(alphaComp);
         g.fillRect(0,0,200,100);
         g.setComposite(oldComp);
<<OTHER STUFF DRAWN HERE>>
      }Any tips would be greatly appreciated thanks.

Answer 1

Create a BufferedImage like this:
int width = 200;
int height = 200;
BufferedImage yourImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);