Merge parent and child one to many in spring web flux using mono, parent updating and child not update?

Question

public void update(AdmWeightageDefinitionDBO t) { sessionFactory.withTransaction((session, tx) -> session.merge(t)).subscribeAsCompletionStage(); }

Answer 1

   //fetch parent and childs
   public Mono < AdmWeightageDefinitionDBO > edit(int id) {
       String str = "select bo from AdmWeightageDefinitionDBO bo " +
           " left join fetch bo.admWeightageDefinitionDetailDBOsSet " +
           " left join fetch bo.admWeightageDefinitionGeneralDBOsSet " +
           " left join fetch bo.admWeightageDefinitionLocationCampusDBOsSet " +
           " where bo.recordStatus = 'A' and bo.id=:id ";
       return Mono.fromFuture(sessionFactory.withSession(session - > session.createQuery(str, AdmWeightageDefinitionDBO.class)
           .setParameter("id", id).getSingleResult()).subscribeAsCompletionStage());
   }

   public Mono < ApiResult > saveOrUpdate(Mono < AdmWeightageDefinitionDTO > dto, String userId) {
       Mono < AdmWeightageDefinitionDTO > mono = dto
           .handle((admWeightageDefinitionDTO, synchronousSink) - > {
               boolean istrue = weightageDefinitionSettingsTransaction.duplicateCheck(admWeightageDefinitionDTO);
               if (istrue) {
                   synchronousSink.error(new DuplicateException("duplicate"));
               } else {
                   synchronousSink.next(admWeightageDefinitionDTO);
               }
           }).cast(AdmWeightageDefinitionDTO.class);
       return mono.map(data - > convertFunc.apply(data, userId))
           .flatMap(t - > {
               return t.flatMap(item - > {
                   //save parent and child try to merge
                   weightageDefinitionSettingsTransaction.update(item);
                   return Mono.just(Boolean.TRUE);
               });
           }).map(Utils::responseResult);
   }

   public BiFunction < AdmWeightageDefinitionDTO, String, Mono < AdmWeightageDefinitionDBO >> convertFunc = (dto, userId) - > {
       if (!Utils.isNullOrEmpty(dto.getId())) {
           // get parent and child and modifing new childs adding and updating existing 
           return weightageDefinitionSettingsTransaction.edit(dto.getId()).map(dbo - > {
               if (!Utils.isNullOrEmpty(dto.getOverallTotal())) {
                   dbo.setOverallTotal(dto.getOverallTotal());
               }
               if (!Utils.isNullOrEmpty(dto.getPreRequisiteWeigtageTotal())) {
                   dbo.setPreRequisiteWeigtageTotal(dto.getPreRequisiteWeigtageTotal());
               }
               if (!Utils.isNullOrEmpty(dto.getEducationWeightageTotal())) {
                   dbo.setEducationWeightageTotal(dto.getEducationWeightageTotal());
               }
               if (!Utils.isNullOrEmpty(dto.getErpAcademicYearDTO()) && !Utils.isNullOrEmpty(dto.getErpAcademicYearDTO().getValue())) {
                   ErpAcademicYearDBO erpAcademicYearDbo = new ErpAcademicYearDBO();
                   erpAcademicYearDbo.setId(Integer.parseInt(dto.getErpAcademicYearDTO().getValue()));
                   dbo.setErpAcademicYearDBO(erpAcademicYearDbo);
               }
               if (!Utils.isNullOrEmpty(dto.getErpProgrammeDTO()) && !Utils.isNullOrEmpty(dto.getErpProgrammeDTO().getValue())) {
                   ErpProgrammeDBO erpProgrammeDBO = new ErpProgrammeDBO();
                   erpProgrammeDBO.setId(Integer.parseInt(dto.getErpProgrammeDTO().getValue()));
                   dbo.setErpProgrammeDBO(erpProgrammeDBO);
               }
               if (!Utils.isNullOrEmpty(dto.getId()))
                   dbo.setModifiedUsersId(Integer.parseInt(userId));
               else
                   dbo.setCreatedUsersId(Integer.parseInt(userId));
               dbo.setRecordStatus('A');
               Set < AdmWeightageDefinitionDetailDBO > weightageDefinitionDetailDBOsSet = dbo.getAdmWeightageDefinitionDetailDBOsSet();

               Set < AdmWeightageDefinitionGeneralDBO > set = dbo.getAdmWeightageDefinitionGeneralDBOsSet();
               Set < AdmWeightageDefinitionGeneralDBO > setNew = new HashSet < AdmWeightageDefinitionGeneralDBO > ();
               set.forEach(item - > {
                   dto.getAdmWeightageDefinitionGeneralDTOsSet().forEach(itemP - > {
                       itemP.getErpReservationCategoryDTOList().forEach(itemR - > {
                           if (!Utils.isNullOrEmpty(item.getId()) && !Utils.isNullOrEmpty(itemR.getParentId()) && item.getId().equals(itemR.getParentId())) {
                               AdmWeightageDefinitionGeneralDBO generalDBO = new AdmWeightageDefinitionGeneralDBO();
                               generalDBO.setAdmWeightageDefinitionDBO(dbo);
                               generalDBO.setErpReservationCategoryDBO(new ErpReservationCategoryDBO());
                               ErpReservationCategoryDBO erpReservationCategoryDBO = new ErpReservationCategoryDBO();
                               erpReservationCategoryDBO.setId(3);
                               generalDBO.setErpReservationCategoryDBO(erpReservationCategoryDBO);
                               generalDBO.setScore(40);
                               setNew.add(generalDBO);
                           }
                       });
                   });
               });
               dbo.setAdmWeightageDefinitionGeneralDBOsSet(setNew);
               //               return ConvertDtoToDBO(dbo1, dto, userId);
               return dbo;
           });
       } else {
           return Mono.just(ConvertDtoToDBO(new AdmWeightageDefinitionDBO(), dto, userId));
       }
   };
   //merge parent and childern
   public void update(AdmWeightageDefinitionDBO t) {
       sessionFactory.withTransaction((session, tx) - > session.merge(t)).subscribeAsCompletionStage();
   }
   // not merging new child and existing child different object not updating