对数据库中某字段的数据进行截取

1、Controller：

@GetMapping("/pisplanstatus")
public Result pisPlanStatus(String queryType) {
    Station station = getStation();
    List<GuideScreenTest> pisplanstatus = (List<GuideScreenTest>) planBriService.pisplanstatus(queryType, station.getStationName());
    for (GuideScreenTest guideScreenTest : pisplanstatus) {
        String ledName = guideScreenTest.getLedName();
        int indx = ledName.indexOf("台");
        String substring = ledName.substring(0,indx+1);
        guideScreenTest.setRegion(substring);
    }
    return Result.ok(pisplanstatus);
}

2、service：

Object pisplanstatus(String queryType, String stationName);

3、serviceImpl：

@Override
    public Object pisplanstatus(String queryType, String stationName) {
//        String sql = "SELECT device_name,ip,station,`status`,fault_state_code,device_address as region,modify_time "+
//                "FROM `guide_screen_monitoring` WHERE station=:stationName ORDER BY modify_time DESC  ";
        String sql = "SELECT gsm.device_name,gsm.ip,gsm.station,gsm.`status`,gsm.fault_state_code,gsm.device_address AS region,gsm.modify_time,rd.s_device_id "+
                " FROM guide_screen_monitoring gsm LEFT JOIN rec_device rd on gsm.ip = rd.s_ip WHERE station=:stationName ORDER BY modify_time DESC  ";
        Map<String, Object> param = new HashMap<>();
        param.put("stationName", stationName);
        List<GuideScreenTest> listBySql = planBrightnessDao.findListBySql(GuideScreenTest.class, sql, param);

    return listBySql;
}