docs: @Nonnull
    public FineUploader5Request setTotalFileSizeName (@Nonnull @Nonempty final String sTotalFileSizeName)
    {
      ValueEnforcer.notEmpty (sTotalFileSizeName, "TotalFileSizeName");
      m_sRequestTotalFileSizeName = sTotalFileSizeName;
      return this;
    }