public void write(byte b[], int off, int len) throws IOException {
        out.write(b, off, len);
        messageDigest.update(b, off, len);
    }
public void write ( byte b [ ] , int off , int len ) throws IOException { out . write ( b , off , len ) ; messageDigest . update ( b , off , len ) ; }
@see OutputStream#write(byte[], int, int)