public interface Checksum {    /**     * Updates the current checksum with the specified byte.     */    public void update(int b);    /**     * Updates the current checksum with the specified array of bytes.     */    public void update(byte[] b, int off, int len);    /**     * Returns the current checksum value.     */    public long getValue();    /**     * Resets the checksum to its initial value.     */    public void reset();}