ImageIO.createImageInputStream Keeps Returns null

Question

Hey, Whenever I try to get an object ImageInputStreamusing ImageIO.createImageInputStream, it just returns nullwithout exceptions, warnings or errors. I tried passing different types of data to a function, simple Fileand InputStream, but both returned null. The documentation states that if no suitable ImageInputStreamSpione is found, the function will return null, but the file is a standard JPEG format, and, of course, does Java come with a service provider for that format out of the box? Thank you for your time.

/**
 * Reads in an image from a file and returns the image in a
 * {@code BufferedImage} object.
 *
 * @param source the file to create the {@code BufferedImage}
 * from.
 * @return the {@code BufferedImage} object representing the image
 * in {@code source}.
 */
private BufferedImage readImage( File source ) {
    // There is only one image in this file
    final int imageIndex = 0;
    BufferedImage image = null;

    try {
        // Get the ImageReader object for this filetype
        Iterator readers =
            ImageIO.getImageReaders( source );
        ImageReader reader = (ImageReader) readers.next();

        // Create an ImageInputStream object from the source image file
        ImageInputStream iis = ImageIO.createImageInputStream( source );
        // Raises IllegalArgumentException, because iis is null
        reader.setInput( iis, true );

        // Read the image file
        image = reader.read( imageIndex );
    } catch ( Exception exception ) {
        exception.printStackTrace();
        System.exit( -1 );
    }

    return image;
}

Answer 1

Why are you doing this? you can just do this:

image = ImageIO.read(source);

Iterators, ImageInputStreams... !

EDIT. , , File ImageIO.getImageReaders() ImageInputStream. :

ImageInputStream iis = ImageIO.createImageInputStream(source);
Iterator readers = ImageIO.getImageReaders(iis);
ImageReader reader = (ImageReader) readers.next();

reader.setInput(iis, false);
image = reader.read(imageIndex);