Why does bufferedimage saved as jpeg sometimes appear black?

Question

Hi, when I save a double Bufferedimage as a jpeg it is often saved as a black square, using:
File file = new File(path, "test.jpg");           
ImageIO.write((BufferedImage) buffer,"jpg",file);and
FileOutputStream out = new FileOutputStream(file);
JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
JPEGEncodeParam param= encoder.getDefaultJPEGEncodeParam((BufferedImage)buffer);
encoder.setJPEGEncodeParam(param);
encoder.encode((BufferedImage)buffer);
out.flush();
out.close();The Bufferedimage always displays correctly in a JFrame. When using ImageIO it often saves correctly, when using FileOutputStream it usually saves as black.
Can anyone explain what is happening? Thanks in advance.

Answer 1

Nope, just that ImageIO is the supported way to do it, and there are not guarentees from Sun that the other way will continue to work.