当我在春季提交休眠交易时，我遇到错误，有人可以帮我吗

Question

当我提交事务时，会出现此异常。 调用org.hibernate.internal.util.compare.ComparableComparator比较方法，由于两个对象均为null，因此它提供了nullpointer异常。 我不明白为什么要调用ComparableComparator？

  

存储库类
  发生这种情况的原因可能是对循环中的实体进行了一些更新，但没有得到实际的根本原因。

with open('myFile.json', 'r') as f:
for line in f:
    tweet = json.loads(line) 
    print(json.dumps(tweet, indent=4))

  

异常堆栈跟踪

 @Repository
@SuppressWarnings("unchecked")
public class AccountingMigrationDaoImpl implements IAccountingMigrationDao{

@Autowired
private SessionFactory sessionFactory;

@Autowired
private DozerBeanMapper mapper;

@Override
public void compairAndAddWithReservedVoucherList(Integer companyId, List<VoucherTypeMasterDto> listVoucherTypeMasterDtos) {
    List<VoucherTypeMaster> listVoucherTypeMasters = null;
    List<VoucherTypeMasterDto> rejectedReservedList = new ArrayList<VoucherTypeMasterDto>();
    List<VoucherTypeMasterDto> additionalVoucherList = new ArrayList<VoucherTypeMasterDto>();
    List<MigrationVoucherTypeMaster> listMigrationVoucherTypeMasters = new ArrayList<MigrationVoucherTypeMaster>();

    try {
        //---- Get Reserved Voucher List For updating its info against company ------//
        listVoucherTypeMasters = sessionFactory.getCurrentSession().getNamedQuery("GET_RESERVED_VOUCHER_LIST").list();
        for (VoucherTypeMasterDto voucherTypeMasterDto : listVoucherTypeMasterDtos) {

            //---- Find and update reserve voucher list given from tally voucher list -----//
            Optional<VoucherTypeMaster> matchingVoucher = listVoucherTypeMasters.stream()
                     .filter(item -> item.getReserveVoucherName().equalsIgnoreCase(voucherTypeMasterDto.getReserveVoucherName()))
                     .findFirst();
            VoucherTypeMaster voucher = matchingVoucher.orElse(null);

            if(voucher != null){
                CompanyVoucherTypeMppr comVoucherTypeMppr = mapper.map(voucherTypeMasterDto.getListCompanyVoucherTypeMpprs().get(0), CompanyVoucherTypeMppr.class,"CompanyVoucherTypeMapperMigration");

                CompanyVoucherTypeMpprId companyTypeMpprId = new CompanyVoucherTypeMpprId();
                companyTypeMpprId.setCompanyId(companyId);
                companyTypeMpprId.setVoucherTypeId(voucher.getVoucherTypeId());
                comVoucherTypeMppr.setCompanyVoucherTypeMpprId(companyTypeMpprId);

                comVoucherTypeMppr.setUseEffectiveDatesForVoucher('Y');
                comVoucherTypeMppr.setIsPrinting('N');
                comVoucherTypeMppr.setStatus('A');
                sessionFactory.getCurrentSession().update(comVoucherTypeMppr);

                MigrationVoucherTypeMaster migrationTypeMaster = new MigrationVoucherTypeMaster();
                migrationTypeMaster.setCompanyId(companyId);
                migrationTypeMaster.setvActualId(voucher.getVoucherTypeId());
                migrationTypeMaster.setvTypeName(voucherTypeMasterDto.getVoucherTypeName());

                sessionFactory.getCurrentSession().saveOrUpdate(migrationTypeMaster);

                listMigrationVoucherTypeMasters.add(migrationTypeMaster);
                //---- Ignore extra reserve voucher from tally ----//
            }else if(voucherTypeMasterDto.getReserveVoucherName() != null && !voucherTypeMasterDto.getReserveVoucherName().equalsIgnoreCase("")){
                rejectedReservedList.add(voucherTypeMasterDto);

                //---- Vouchers list except reserve and extra reserve
            }else if(voucherTypeMasterDto.getReserveVoucherName().equalsIgnoreCase("")){
                additionalVoucherList.add(voucherTypeMasterDto);
            }
        }

        for (VoucherTypeMasterDto voucherTypeMasterDto : additionalVoucherList) {
            //------- Checking extra voucher from tally which are not belongs to or childs from rejected voucher list ---//
            Optional<VoucherTypeMasterDto> matchingVoucherDto = rejectedReservedList.stream()
                     .filter(item -> item.getVoucherTypeName().equalsIgnoreCase(voucherTypeMasterDto.getParentVouhcerName()))
                     .findFirst();
            VoucherTypeMasterDto voucherDto = matchingVoucherDto.orElse(null);

            if(voucherDto == null){
                VoucherTypeMaster voucherTypeMaster = mapper.map(voucherTypeMasterDto, VoucherTypeMaster.class,"VoucherMasterDtoTOVoucherMasterMigration");

                Optional<MigrationVoucherTypeMaster> matchingVoucher = listMigrationVoucherTypeMasters.stream()
                         .filter(item -> item.getvTypeName().equalsIgnoreCase(voucherTypeMasterDto.getParentVouhcerName()))
                         .findFirst();
                MigrationVoucherTypeMaster voucher = matchingVoucher.orElse(null);

                voucherTypeMaster.setSuperVoucherTypeId(voucher.getvActualId());
                voucherTypeMaster.setCreatedBy(1);
                voucherTypeMaster.setCreatedDate(new Date().getTime());
                voucherTypeMaster.setIsPrimaryVoucher('N');
                voucherTypeMaster.setReserveVoucherName(null);

                CompanyVoucherTypeMppr companyVoucherTypeMppr = voucherTypeMaster.getListCompanyVoucherTypeMpprs().get(0);
                companyVoucherTypeMppr.setUseEffectiveDatesForVoucher('N');
                companyVoucherTypeMppr.setIsPrinting('N');
                companyVoucherTypeMppr.setStatus('Y');

                CompanyVoucherTypeMpprId companyTypeMpprId = new CompanyVoucherTypeMpprId();
                companyTypeMpprId.setCompanyId(companyId);
                companyVoucherTypeMppr.setCompanyVoucherTypeMpprId(companyTypeMpprId);
                sessionFactory.getCurrentSession().saveOrUpdate(voucherTypeMaster);

                companyTypeMpprId.setVoucherTypeId(voucherTypeMaster.getVoucherTypeId());
                sessionFactory.getCurrentSession().saveOrUpdate(companyVoucherTypeMppr);

                MigrationVoucherTypeMaster migrationTypeMaster = new MigrationVoucherTypeMaster();
                migrationTypeMaster.setCompanyId(companyId);
                migrationTypeMaster.setvActualId(voucherTypeMaster.getVoucherTypeId());
                migrationTypeMaster.setvTypeName(voucherTypeMaster.getVoucherTypeName());

                sessionFactory.getCurrentSession().saveOrUpdate(migrationTypeMaster);
                listMigrationVoucherTypeMasters.add(migrationTypeMaster);

            }
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
}
}