init static method
      
void
init()
      
     
    
    
Implementation
static void init() {
  if (_isInit) return;
  _isInit = true;
  int p = 1;
  for (int i = 0; i < 255; i++) {
    _aLog[i] = p;
    _log[p] = i;
    p *= 2;
    if (p >= 256) {
      p ^= _moduloValue;
    }
  }
}