Aggregate identifier must be non-null

Aggregate identifier must be non-null after applying an event. Make sure the aggregate identifier is initialized at the latest when handling the creation event.

For this I have force fully passed a random variable to CreateRemarkCommand() which is given below: Users.kt class CreateRemarkEvent(val id: Int, val remarkDto: RemarkDto) : BaseEvent(); class CreateRemarkCommand(val id: Int, val remarkDto: RemarkDto) : BaseCommand(); RemarksController: public BaseResponseDto storeRemarks(@RequestBody RemarkDto remarkDto){ remarkDto.setRemarkDate(new Date()); remarkDto.setUserType(UserType.SUBSCRIBER); int remarkAggregate = Integer.parseInt(RandomStringUtils.randomNumeric(6).toString()); CreateRemarkCommand remarkCommand = new CreateRemarkCommand(remarkAggregate, remarkDto); commandBus.dispatch(new GenericCommandMessage<>(remarkCommand)); log.info("Dispatched command"); return BaseResponseDto.builder() .statusCode(StatusCode.SUCCESS) .message("Remarks Created.") .build(); } EventSourcingHandler: @EventSourcingHandler public void on(CreateRemarkEvent event) { RemarkDto remarkDto = event.getRemarkDto(); this.id = event.getId(); this.adminId = remarkDto.getAdminId(); this.userId = remarkDto.getUserId(); this.userType = remarkDto.getUserType(); this.remark = remarkDto.getRemark(); this.remarkDate = remarkDto.getRemarkDate(); } @EventHandler: @EventHandler public void handle(CreateRemarkEvent event) { RemarkDto remarkDto = event.getRemarkDto(); UserRemarks remarks = new UserRemarks(); remarks.setUserId(remarkDto.getUserId()); remarks.setAdminId(remarkDto.getAdminId()); remarks.setUserType(remarkDto.getUserType()); remarks.setRemark(remarkDto.getRemark()); remarks.setRemarkDate(remarkDto.getRemarkDate()); remarksQueryRepository.save(remarks); log.info("Successfully saved remarks of user Id" + remarkDto.getUserId()); } @CommandHandler: @CommandHandler public void handle(CreateRemarkCommand command) throws Exception { remarksRepository.newInstance(() -> new UserRemarks(command.getId(), command.getRemarkDto())); } RemarkAggregate: public class UserRemarks { @AggregateIdentifier private Integer id; private String remark; private Integer adminId; private Integer userId; private UserType userType; private Date remarkDate; public UserRemarks(int id, RemarkDto remarkDto) { apply(new CreateRemarkEvent(id, remarkDto)); }