code: public int compareTo(TextIntWritable o) {
          int c = t.compareTo(o.t);
          if (c != 0)
              return c;
          return position - o.position;
      }
docs: Returns the a negative value if the provided {@code TextIntWritable} has
  a lexicographically less text value or if its position is less, or
  returns a positive value if the provided {@code TextIntWritable} has text
  with a lexicographically greater value or if its position is larger.