@Override
      public Modification next() {
        if (cachedModification[0] == null) {
          throw new NoSuchElementException();
        }
        Modification result = cachedModification[0];
        cachedModification[0] = null;
        return result;
      }
Construct a LocalTextModificationAccessor using a file specified by filePath.

@param filePath the path of the file that is used for storing modifications.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/storageengine/dataregion/modification/v1/io/LocalTextModificationAccessor.java