code: private boolean exactMatch(String str, int i) {
      int end = str.length() - i;
      for (String p : _patterns) {
        int start = end - p.length();
        if (start >= 0 && str.regionMatches(start, p, 0, p.length())) {
          return true;
        }
      }
      return false;
    }
docs: Check for exact match.
  FIXME:
  @param str
  @param i
  @return