code: public void update(char[] data, int start, int end) {
          int i;
  
          for (i = start; i < end; i++) {
              if (data[i] == '\n') {
                  col = 1;
                  line++;
              } else {
                  col++;
              }
          }
          ofs += (end - start);
      }
docs: the indicated range has been passed by the scanner.