@Override
    public ModEntry next() {
      if (exclusiveModIterator != null && exclusiveModIterator.hasNext()) {
        return exclusiveModIterator.next();
      }
      if (sharedModIterator != null && sharedModIterator.hasNext()) {
        return sharedModIterator.next();
      }
      throw new NoSuchElementException();
    }
@return is this tsfile resource in a TsFileResourceList
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/storageengine/dataregion/tsfile/TsFileResource.java