@Override
	public String getFileExtension()
	{
		switch( getFormat() )
		{
			case FORMAT_XLSX:
				return ".xlsx";
			case FORMAT_XLSM:
				return ".xlsm";
			case FORMAT_XLTX:
				return ".xltx";
			case FORMAT_XLTM:
				return ".xltm";
			case FORMAT_XLS:
				return ".xls";
			default:
				return "";
		}
	}