code: public MetricValue[] getAll(int startInclusive, int endExclusive) {
          return IntStream.range(startInclusive, endExclusive)
                  .mapToObj(this::getOrNull)
                  .toArray(MetricValue[]::new);
      }
docs: Returns metric values at the given range.
  
  Absence of a value is represented by a null value in the array.
  
  @param startInclusive The first index of the range.
  @param endExclusive The past-the-end index of the range.
  @return An array of metric values, with null values representing absence
  of the metric.