@Override
  public void checkSanity(final int record) throws IOException {
    withReadLock(() -> {
      final int size = myRecordsTable.getSize(record);
      final int capacity = myRecordsTable.getCapacity(record);
      final long address = myRecordsTable.getAddress(record);
      final long dataFileSize = myDataTable.getFileSize();
      assert size >= 0 : "[#" + record + "]: size(=" + size + ") must not be negative";
      assert capacity >= 0 : "[#" + record + "]: capacity(=" + capacity + ") -- must NOT be negative";
      assert address >= 0 : "[#" + record + "]: address(=" + address + ") must not be negative";
      assert size <= capacity : "[#" + record + "]: size(=" + size + ") > capacity(=" + capacity + ")";
      assert address + capacity <= dataFileSize
        : "[#" + record + "]: address(=" + address + ")+capacity(=" + size + ") is beyond EOF(=" + dataFileSize + ")";
    });
  }
@Override
  public void checkSanity(final int record)