code: public static Map<Integer, Integer> getRanges(int partition) {
          return instance.get().getSecond().pGetRanges(partition);
      }
docs: Get the ranges the given partition is assigned to.
  @param partition
  @return A map of ranges, the key is the start of a range, the value is
  the corresponding end. Ranges returned in the map are [start, end).
  The ranges may or may not be contiguous.