//日期在lowDate和heightDate之间
    //创建SimpleDateFormat，并设置格式
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
    //lowDate
    String lowDat = "2020-08-10";
    Date lowDate = sdf.parse(lowDat);
    //heightDate
    String heightDat = "2020-08-31";
    Date heightDate = sdf.parse(heightDat);
    //封装
    goodsCondition.setLowDate(lowDate);
    goodsCondition.setHeightDate(heightDate);