update(buffer, 0, buffer.length);
int s1 = checksum & 0xffff; int s2 = checksum >>> 16;  s1 = (s1 + (bval & 0xFF)) % BASE; s2 = (s1 + s2) % BASE;  checksum = (s2 << 16) + s1;
  public void update (byte[] buffer)  {    update(buffer, 0, buffer.length);  }