private static boolean isZeroLengthThenDelete(final FileSystem fs, final FileStatus stat,
    final Path p) throws IOException {
    if (stat.getLen() > 0) {
      return false;
    }
    LOG.warn("File " + p + " is zero-length, deleting.");
    fs.delete(p, false);
    return true;
  }
make sure have been through lease recovery before get file status, so the file length can be
trusted.
@param p File to check.
@return True if file was zero-length (and if so, we'll delete it in here).
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegion.java