@Override
    public Checksum compute(final InputStream in, final TransferStatus status) throws BackgroundException {
        final byte[] digest = this.digest("SHA-256", this.normalize(in, status), status);
        return new Checksum(HashAlgorithm.sha256, digest);
    }
@Test
    public void testCompute() throws Exception {
        assertEquals("e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
            new SHA256ChecksumCompute().compute(new NullInputStream(0), new TransferStatus()).hash);
    }