try {
   IFigure f = getFigure(); //The content EditPart's getFigure() method
   Image image = new Image(Display.getCurrent(), f.getSize().width, f.getSize().height);
   GC gc = new GC(image);
   SWTGraphics graphics = new SWTGraphics(gc);
   f.paint(graphics);

   FileOutputStream fos = new FileOutputStream("in.jpg"); //This will save the image directly on the c: drive
   ImageLoader loader = new ImageLoader();
   loader.data = new ImageData[] { image.getImageData() };
   loader.save(fos, SWT.IMAGE_JPEG); //Several image formats are supported, including bitmap
} catch(NullPointerException n) {
   System.out.println(n); //Probably not needed, but I was getting some errors before I got it working
} catch(IOException e) {
   System.out.println(e);
}