code: protected static List<Intervalable> findOverlappingRanges(IntervalNode node, Intervalable interval)
      {
          if (node != null)
          {
              return node.findOverlaps(interval);
          }
          return Collections.emptyList();
      }
docs: 是对IntervalNode.findOverlaps(Intervalable)的一个包装，防止NPE
  @see com.hankcs.hanlp.algorithm.ahocorasick.interval.IntervalNode#findOverlaps(Intervalable)
  @param node
  @param interval
  @return