У меня учебный проект на Spring MVC и я пытаюсь применить паттерн Chain of responsibility. Создал пакет handler в котором есть интерфейс Handler
public interface Handler { void setRelationship(Relationship relationship, User user, String status, Long userIdTo, Long idUserFrom)throws BadRequestException, InternalServerError; } Абстрактный класс
public abstract class RelationshipHandler implements Handler, Ordered { public abstract void setRelationship(Relationship relationship, User user, String status, Long userIdTo, Long idUserFrom)throws BadRequestException, InternalServerError; boolean checkStatusForChange(Relationship relationship, RelationshipStatusType currentStatus, RelationshipStatusType newStatus, String status){ return relationship != null && relationship.getStatusType().equals(currentStatus) && status.equals(newStatus.toString()); } } От которого наследуются четыре обработчика Первый
@Component public class AcceptedHandler extends RelationshipHandler { private final RelationshipDAO relationshipDAO; @Autowired public AcceptedHandler(RelationshipDAO relationshipDAO) { this.relationshipDAO = relationshipDAO; } @Override public void setRelationship(Relationship relationship, User user, String status, Long idUserTo, Long idUserFrom) throws BadRequestException, InternalServerError{ if (user != null && user.getId().equals(idUserTo) && checkStatusForChange(relationship, RelationshipStatusType.REQUESTED, RelationshipStatusType.ACCEPTED, status)){ relationshipDAO.update(addFriendsByRequest(user, relationship)); } } private Relationship addFriendsByRequest(User user, Relationship relationship) throws BadRequestException, InternalServerError { if (user == null || relationship == null){ throw new BadRequestException("User or relationship is not found."); } if (checkingNumberFriends(user.getId())){ Date acceptedRequest = new Date(); relationship.setAcceptedFriends(acceptedRequest); relationship.setStatusType(RelationshipStatusType.ACCEPTED); } else { throw new BadRequestException("Friends limit exceeded."); } return relationship; } private boolean checkingNumberFriends(Long id) throws BadRequestException, InternalServerError { if (id == null){ throw new BadRequestException("ID does not exist."); } return relationshipDAO.getQuantityFriends(id, RelationshipStatusType.ACCEPTED) < 10; } @Override public int getOrder() { return Ordered.HIGHEST_PRECEDENCE; } } Второй
@Component public class DeletedHandler extends RelationshipHandler { private final RelationshipDAO relationshipDAO; @Autowired public DeletedHandler(RelationshipDAO relationshipDAO) { this.relationshipDAO = relationshipDAO; } @Override public void setRelationship(Relationship relationship, User user, String status, Long idUserTo, Long idUserFrom) throws BadRequestException, InternalServerError { if (user != null && (user.getId().equals(idUserFrom) || user.getId().equals(idUserTo)) && checkStatusForChange(relationship, RelationshipStatusType.ACCEPTED, RelationshipStatusType.DELETED, status)){ relationshipDAO.update(delFromFriends(idUserFrom, idUserTo, relationship)); } } private Relationship delFromFriends(Long idUserFrom, Long idUserTo, Relationship relationship) throws BadRequestException, InternalServerError { if (idUserFrom == null || idUserTo == null || relationship == null){ throw new BadRequestException("IdUserFrom or idUserTo or relationship is not found."); } if (checkingAcceptedDate(idUserFrom, idUserTo)){ relationship.setStatusType(RelationshipStatusType.DELETED); relationship.setAcceptedFriends(null); } else { throw new BadRequestException("You can not perform an action delete from friends."); } return relationship; } private boolean checkingAcceptedDate(Long idUserFrom, Long idUserTo) throws BadRequestException, InternalServerError{ if (idUserFrom == null || idUserTo == null){ throw new BadRequestException("IdUserFrom or idUserTo is not found."); } return relationshipDAO.getQuantityHoursAfterAccepted(idUserFrom, idUserTo, RelationshipStatusType.ACCEPTED) >= 3; } @Override public int getOrder() { return 2; } } Третий
@Component public class CanceledHandler extends RelationshipHandler { private final RelationshipDAO relationshipDAO; @Autowired public CanceledHandler(RelationshipDAO relationshipDAO) { this.relationshipDAO = relationshipDAO; } @Override public void setRelationship(Relationship relationship, User user, String status, Long idUserTo, Long idUserFrom) throws BadRequestException, InternalServerError { if (user != null && user.getId().equals(idUserFrom) && checkStatusForChange(relationship, RelationshipStatusType.REQUESTED, RelationshipStatusType.CANCELED, status)){ relationship.setStatusType(RelationshipStatusType.CANCELED); relationshipDAO.update(relationship); } } @Override public int getOrder() { return 3; } } И четвертый
@Component public class DeclinedHandler extends RelationshipHandler { private final RelationshipDAO relationshipDAO; @Autowired public DeclinedHandler(RelationshipDAO relationshipDAO) { this.relationshipDAO = relationshipDAO; } @Override public void setRelationship(Relationship relationship, User user, String status, Long idUserTo, Long idUserFrom) throws BadRequestException, InternalServerError { if (user != null && user.getId().equals(idUserTo) && checkStatusForChange(relationship, RelationshipStatusType.REQUESTED, RelationshipStatusType.DECLINED, status)) { relationship.setStatusType(RelationshipStatusType.DECLINED); relationshipDAO.update(relationship); } } @Override public int getOrder() { return 1; } } Класс в котором строю цепочку
@Component public class HandlerForUser { @Autowired private List<Handler> handlers; @PostConstruct public void init(){ handlers.sort(INSTANCE); } public void execute(Relationship relationship, User user, String status, Long idUserTo, Long idUserFrom)throws BadRequestException, InternalServerError { for (Handler handler : handlers){ handler.setRelationship(relationship, user, status, idUserTo, idUserFrom); } } } И использую это в сервисе:
@Service public class RelationshipService { private RelationshipDAO relationshipDAO; private UserDAO userDAO; private HandlerForUser handlerForUser; @Autowired public RelationshipService(RelationshipDAO relationshipDAO, UserDAO userDAO, HandlerForUser handlerForUser) { this.relationshipDAO = relationshipDAO; this.userDAO = userDAO; this.handlerForUser = handlerForUser; } public void setRelationship(String userIdTo, String userIdFrom, HttpSession session)throws BadRequestException, InternalServerError{ User userFrom = (User) session.getAttribute(userIdFrom); if (userFrom == null){ throw new BadRequestException("User with ID " + userIdFrom + " is not logged in."); } User userTo = userDAO.findById(Long.parseLong(userIdTo)); if (userTo == null){ throw new BadRequestException("User with ID " + userIdTo + " is not found in DB."); } Relationship relationshipFind = relationshipDAO.getRelationship(userFrom.getId(), userTo.getId()); try { if (relationshipFind == null){ Relationship relationship = new Relationship(); relationship.setUserFrom(userFrom); relationship.setUserTo(userTo); relationship.setStatusType(RelationshipStatusType.REQUESTED); save(sendRequest(Long.parseLong(userIdFrom), relationship)); } else if (relationshipFind.getStatusType().equals(RelationshipStatusType.CANCELED) || relationshipFind.getStatusType().equals(RelationshipStatusType.DECLINED) || relationshipFind.getStatusType().equals(RelationshipStatusType.DELETED)){ relationshipFind.setStatusType(RelationshipStatusType.REQUESTED); relationshipDAO.update(sendRequest(Long.valueOf(userIdFrom), relationshipFind)); } else { throw new BadRequestException("Something is wrong with the input."); } }catch (InternalServerError e) { throw new InternalServerError("Something went wrong..."); } } public void setRelationshipByStatus(String status, String userIdTo, String userIdFrom, HttpSession session) throws BadRequestException, InternalServerError { if (status == null || userIdTo == null || userIdFrom == null){ throw new BadRequestException("Status or userIdTo or userIdFrom is not exist."); } User userFrom = (User) session.getAttribute(userIdFrom); User userTo = (User) session.getAttribute(userIdTo); Relationship relationshipFind = relationshipDAO.getRelationship(Long.valueOf(userIdFrom), Long.valueOf(userIdTo)); try { if (userTo != null){ handlerForUser.execute(relationshipFind, userTo, status, Long.valueOf(userIdTo), Long.valueOf(userIdFrom)); } if (userFrom != null){ handlerForUser.execute(relationshipFind, userFrom, status, Long.valueOf(userIdTo), Long.valueOf(userIdFrom)); } else { throw new BadRequestException("Something is wrong with the input. Method setRelationshipByStatus"); } }catch (InternalServerError e) { throw new InternalServerError("Something went wrong..."); } } public void validationInputData(String idUserFrom, String idUserTo, HttpSession session)throws BadRequestException{ if (idUserFrom == null || idUserTo == null){ throw new BadRequestException("UserFrom or userTo does not exist."); } if (idUserFrom.equals(idUserTo)){ throw new BadRequestException("Actions between the same user are not possible."); } if (session == null){ throw new BadRequestException("Session is not exist."); } } private Relationship save(Relationship relationship)throws BadRequestException { if (relationship != null && relationship.getId() != null){ throw new BadRequestException("This Relationship with ID - " + relationship.getId() + " can not save in DB."); } else { relationshipDAO.save(relationship); } return relationship; } private Relationship sendRequest(Long idUser, Relationship relationship) throws BadRequestException, InternalServerError { if (idUser == null || relationship == null){ throw new BadRequestException("User or relationship is not found."); } if (checkingNumberRequested(idUser)){ relationship.setStatusType(RelationshipStatusType.REQUESTED); } else { throw new BadRequestException("Limit on sent requests exceeded."); } return relationship; } private boolean checkingNumberRequested(Long id) throws BadRequestException, InternalServerError{ if (id == null){ throw new BadRequestException("ID does not exist."); } return relationshipDAO.getQuantityRequests(id, RelationshipStatusType.REQUESTED) < 10; } } Сейчас получается, что запрос проходит по всему списку обработчиков не прерывая цепочку если запрос обработался успешно. Может я структуру построил не правильно. Наверное в абстрактном классе надо задать поведение для передачи ссылки на следующий обработчик. Что-то ни как не соображу, что делать дальше… Помогите разобраться, как правильно построить цепочку
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