code: public static final List<Map.Entry<Double, Double>> encode(final Map<Double, Double> keyRanges) {
          Preconditions.checkNotNull(keyRanges, "keyRanges");
  
          return keyRanges
                  .entrySet()
                  .stream()
                  .map(x -> new AbstractMap.SimpleEntry<>(x.getKey(), x.getValue()))
                  .collect(Collectors.toList());
      }
docs: Return list of key ranges available.
  
  @param keyRanges List of Key Value pairs.
  @return Collection of key ranges available.