docs: public static <T> ItemsSketch<T> getInstance(final int k, final Comparator<? super T> comparator) {
      final ItemsSketch<T> qs = new ItemsSketch<>(k, comparator);
      final int bufAlloc = 2 * Math.min(DoublesSketch.MIN_K, k); //the min is important
      qs.n_ = 0;
      qs.combinedBufferItemCapacity_ = bufAlloc;
      qs.combinedBuffer_ = new Object[bufAlloc];
      qs.baseBufferCount_ = 0;
      qs.bitPattern_ = 0;
      qs.minValue_ = null;
      qs.maxValue_ = null;
      return qs;
    }