@Override public boolean has(Pattern pattern){
  final Matcher matcher=pattern.matcher(rest());
  return matcher.find() && matcher.start() == 0;
}

@ Override public boolean has ( Pattern pattern ) { final Matcher matcher = pattern . matcher ( rest ( ) ) ; return matcher . find ( ) && matcher . start ( ) == 0 ; }
this method will determine whether the indicated pattern can be found at this point in the document or not
