@Override
  public @NotNull DataExternalizer<Integer> getValueExternalizer() {
    return new DataExternalizer<>() {
      @Override
      public void save(@NotNull DataOutput out, Integer value) throws IOException {
        DataInputOutputUtil.writeINT(out, value);
      }

      @Override
      public Integer read(@NotNull DataInput in) throws IOException {
        return DataInputOutputUtil.readINT(in);
      }
    };
  }
@Override
  public @NotNull DataExternalizer<Integer> getValueExternalizer()