I am studying spring-boot and JPA. the spring-boot version is 2.6.3, which is the latest current version.
I defined my entity class like:
#Entity
public class Author implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private int age;
private String name;
private String genre;
// ignore the getters, setters and toString()
And defined with one projection DTO interface.
public interface AuthorDto {
public String getName();
public int getAge();
}
then defined the repository as follows:
#Repository
public interface AuthorRepository extends JpaRepository<Author, Long> {
Author findFirstByGenre(String genre);
AuthorDto findTopByGenre(String genre);
}
the method findFirstByXXX worked well, but the second method, AuthorDto findTopByGenre(String genre);, could not work well, and was ended up with the following error in the log:
Reason: Failed to create query for method public abstract com.bookstore.dto.AuthorDto com.bookstore.repository.AuthorRepository.findTopByGenre(java.lang.String)! Cannot invoke "java.lang.Class.isInterface()" because "typeToRead" is null; nested exception is java.lang.IllegalArgumentException: Failed to create query for method public abstract com.bookstore.dto.AuthorDto com.bookstore.repository.AuthorRepository.findTopByGenre(java.lang.String)! Cannot invoke "java.lang.Class.isInterface()" because "typeToRead" is null
I tested the same code on spring-boot 2.1.4.RELEASE, it could work well.
I tried to find any official documents on this, but didn't find useful thread on this.
Related
I am new to using nosql databases, specifically mongodb.
My project is based on spring data jpa (postgresql). I would like to know if it is possible to use posgresql and mongodb together? I would like to take data from a postgresql database and write it to mongodb so as not to load postgre.
My Entity for mongodb
#Data
#Document(collection = "exposure")
public class Exposure {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#ManyToOne
#NotNull
private Facility facility;
#ManyToOne
#NotNull
private Investee investee;
#ManyToOne
#NotNull
private Investee investeeName;
#ManyToOne
#NotNull
private Tranche tranche;
}
Repository
#Repository
public interface ExposureRepository extends MongoRepository<Exposure, Long> {
}
DtoService
#Service
#RequiredArgsConstructor
public class DefaultExplosureDtoService implements ExplosureDtoService {
private final FacilityService facilityService;
private final InvesteeService investeeService;
private final ExplosureMapper explosureMapper;
private final ExplosureService explosureService;
#Override
#Transactional
public ExplosureDto create(CreateExplosureDto explosureDto) {
Explosure explosure = new Explosure();
if (explosureDto.getFacilityId() != null) {
explosure.setFacility(facilityService.getById(explosureDto.getFacilityId()));
}
if (explosureDto.getInvesteeId() != null) {
explosure.setInvestee(investeeService.getById(explosureDto.getInvesteeId()));
}
Explosure savedExplosure = explosureService.save(explosure);
return explosureMapper.toExplosureDto(savedExplosure);
}
}
Service
#Service
#RequiredArgsConstructor
public class DefaultExplosureService implements ExplosureService {
private final ExplosureRepository explosureRepository;
#Override
public Explosure save(Explosure explosure) {
return explosureRepository.save(explosure);
}
}
When I run the application, I get a 405 error. And I can’t figure out how to take data from the postgres database and write it to mongodb
I'm new to Mapstruct and I'm trying to understand it properly.
What I want to achieve is converting from a DTO String parameter (carModel) to his Entity, retrieve using Service and Repository.
The problem is that Mapper class generated by Mapstruct is trying to inject the Service class with #Autowired annotation, but it's not working. The service is null.
Here's my #Mapper class:
#Mapper(componentModel = "spring", uses = CarModelService.class)
public interface KitMapper extends EntityMapper<KitDTO, Kit> {
KitMapper INSTANCE = Mappers.getMapper(KitMapper.class);
#Mapping(source = "weight", target = "systemWeight")
#Mapping(source = "carModel", target = "carModel")
Kit toEntity(KitDTO kitDTO);
}
public interface EntityMapper<D, E> {
E toEntity(D dto);
List<E> toEntity(List<D> dtoList);
}
The #Service class:
#Service
#Transactional
public class CarModelService {
private final CarModelRepository carModelRepository;
#Transactional(readOnly = true)
public CarModel findByName(String name) {
return carModelRepository.findByName(name).orElse(null);
}
}
The #Repository class:
#Repository
public interface CarModelRepository extends JpaRepository<CarModel, Long> {
Optional<CarModel> findByName(String carModelName);
}
The DTO and Entity classes:
public class KitDTO {
private String id;
private String carModel; // e.g. "Ferrari Monza"
....
}
#Entity
#Table(name = "kit")
public class Kit implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "sequenceGenerator")
#SequenceGenerator(name = "sequenceGenerator")
#Column(name = "id")
private Long id;
#ManyToOne
private CarModel carModel;
...
}
#Entity
#Table(name = "car_model")
public class CarModel implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "sequenceGenerator")
#SequenceGenerator(name = "sequenceGenerator")
#Column(name = "id")
private Long id;
#Column(name = "name")
private String name;
...
}
The build work properly but the application stop when I try to use the Mapper. It says that carModelService is null.
Here's the mapper generated implementation class:
#Component
public class KitMapperImpl implements KitMapper {
#Autowired // <-- this seems not working
private CarModelService carModelService;
#Override
public Kit toEntity(KitDTO kitDTO) {
if ( kitDTO == null ) {
return null;
}
Kit kit = new Kit();
kit.setSystemWeight( String.valueOf( kitDTO.getWeight() ) );
kit.carModel( carModelService.findByName(kitDTO.getCarModel()) ); // <-- carModelService is null!
// other setters
return kit;
}
}
I've tried many things, using Decorator, #Context, expression, inject the #Mapper class into the #Service class.
I've found many questions but actually no one helped me:
Mapstruct - How can I inject a spring dependency in the Generated Mapper class
#Service Class Not Autowired in org.mapstruct.#Mapper Class
MapStruct mapper not initialized with autowired when debug
Any help would be appreciated! Thanks in advance!
Found the solution!
Instead of calling directly the Mapper method toEntity() from the #RestController class, I injected the mapper in the CarModelService class and created a method that call the mapper.
In this way the flow is:
Controller --> Service --> Mapper
#Service
#Transactional
public class KitService {
private final KitRepository kitRepository;
private final KitSearchRepository kitSearchRepository;
private final KitMapper kitMapper; // <-- mapper declaration
public KitService(KitRepository kitRepository, KitSearchRepository kitSearchRepository, KitMapper kitMapper) {
this.kitRepository = kitRepository;
this.kitSearchRepository = kitSearchRepository;
this.kitMapper = kitMapper; // <-- mapper initilization
}
// here the method which calls mapper
public Kit convertDTOToEntity(KitDTO kitDTO) {
return kitMapper.toEntity(kitDTO);
}
In this way, the generated class by Mapstruct doesn't give error on the CarModelService.
Seems like this approach is the only way to achieve this, create a king of "bridge" between services and mappers.
(You can use also the #Autowired annotation instead of constructor)
Can you please share the error message?
From the information that you shared, I can see the carModel in KitDto is String and in Entity is CarModel class. Not sure how mapstruct's auto generated implementation class implemented this: kit.carModel( carModelService.findByName(kitDTO.getCarModel()) );.
But I would like to share another approach,Don't know this is a best practice or not. In this approach you can create a abstarct class of mapper, in which you can #Autowired repository can manually add those mapping.
I shared the snippet for it. Hopefully this will help you.
#Mapper(componentModel = "spring", nullValuePropertyMappingStrategy = NullValuePropertyMappingStrategy.IGNORE)
public abstract class ProductMapper {
#Autowired
private CarModelService carModelService;
public abstract Kit convertDTOToEntity(KitDTO kitDTO);
public Kit toEntity(KitDTO kitDTO);
{
Kit kit = convertDTOToEntity(kitDTO);
kit.setCarModel(carModelService.findByName(kitDTO.getCarModel()));
return kit;
}
}
Curious about the other approaches, will follow this thread. We can discuss the best practices
Iam building a simple Spring Boot app, with 2 entities:
- Student model
#Entity
#Data
#AllArgsConstructor
#NoArgsConstructor
public class Student {
#Id #GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private String name;
private String password;
private boolean active;
private Date dob;
private String roles;
#ManyToOne
private Training training;
}
- Training model
#Entity
#Data
#AllArgsConstructor
#NoArgsConstructor
public class Training {
#Id #GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private String name;
private int duration;
#OneToMany(mappedBy = "training")
#JsonIgnore
private Collection<Student> students;
}
EDIT
I run the app by adding 2 resources in the db:
public static void main(String[] args) {
SpringApplication.run(MsSchoolingSbApplication.class, args);
}
#Override
public void run(String... args) throws Exception {
Training t1=trainingRepo.save(new Training(null,"php", 20, null));
Training t2=trainingRepo.save(new Training(null,"java", 20, null));
Student st=new Student(null, "XXXX", "ZZZZ", true,new Date(),"ADMIN",t1);
Student st2=new Student(null, "XXXXX2", "ZZZZZ2", true,new Date(),"USER",t2);
studentRepo.save(st);
studentRepo.save(st2);
}
END EDIT
EDIT 2
- StudentRepo
#RepositoryRestController
public interface StudentRepo extends JpaRepository<Student, Long>{
public List<Student> findByNameStartsWith(String name);
Optional<Student> findByName(String name);
}
- TrainingRepo
#RepositoryRestController
public interface TrainingRepo extends JpaRepository<Training, Long> {
}
END EDIT 2
i've tried to put fetch = FetchType.EAGER or LAZY, i've also added #JsonIgnore but as soon as i fill the db with new data (trainings and students) and run the app, i get this message:
Caused by: org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: com.schooling.models.Training.students, could not initialize proxy - no Session
What am i doing wrong ?
The problem you got must have related to how you use those 2 entities so you need to provide more information about how you use it.
You might want to look out for your problem in this tutorial: https://www.baeldung.com/hibernate-initialize-proxy-exception
Do not use Lombok's #Data annotation on #Entity classes.
Reason: #Data generates hashcode(), equals() and toString() methods that use the generated getters. Using the getter means of course fetching new data even if the property was marked with FetchType=LAZY.
Somewhere along the way hibernate tries to log the data with toString() and it crashes
EDIT
you can exclude the relation from the toString method by adding, for example in my case:
#ToString(exclude = {"students"})
I have a Springboot Application with Repositories having Spring Data JPA Queries like findOne, findAll and also derived ones like findByID or findByName etc.
What I want to achieve is multitenancy. All entities have an "account_id" column which holds the tenant.
How do I add a filter like "account_id" to all the queries metioned above without using derived queries that contains those name slike findIdAndAccountid (which would be findone)
#Repository
public interface CategoryRepository extends JpaRepository<Category, Long> {
Category findByName(String name);
}
Here's the corresponding entity
#Entity
#Table(name = "unit")
#Data
public class Unit {
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
private Long id;
private String name;
#Column(name = "account_id")
private Long account_id;
}
I know most people use schemas as tenant separation but that's impossible for me. Is there a way (I didn't find one) to add such a tenant filter condition on those queries without writing NamedQueries or using DerivedQueries. An elegeant solution like annotate the repository or entity or maybe the queries that all queries should add the additional filter "account_id"?
You can add Where clause on your Entity classes (Didnt had time to test )
#Entity
#Table(name = "unit")
#Data
#Where(clause = "account_id= :account_id")
public class Unit {
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
private Long id;
private String name;
#Column(name = "account_id")
private Long account_id;
}
Update and Solution
1. Create a Filter & FilterDef on the entity like so
#FilterDef(name="accountFilter", parameters=#ParamDef( name="accountId", type="long" ) )
#Filters( {
#Filter(name="accountFilter", condition=":accountId = account_id")
} )
public class Category {
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
private Long id;
private String name;
#Column(name = "account_id")
private Long account_id;
}
enable filtering in the controller by autowiring entitymanager, writing a method to enable the filter and activate the filter in #ModelAttribute for each request
#RestController
#RequestMapping(path = "/categories",produces = MediaType.APPLICATION_JSON_VALUE )
public class CategoryController {
private final CategoryRepository repository;
#Autowired
private EntityManager entityManager;
CategoryController(CategoryRepository repository) {
this.repository = repository;
}
private void activateFilter() {
Session session = entityManager.unwrap(Session.class);
Filter filter = session.enableFilter("accountFilter");
filter.setParameter("accountId", Long.valueOf(TenantContext.getCurrentTenant()));
}
#ModelAttribute
public void initFilter() {
activateFilter();
}
... your rest methods here
}
I have a super Entity class like this:
#Getter
#Setter
#NoArgsConstructor
public class GenericEntity {
#Id
private Long id;
#JsonIgnore
#CreatedBy
private Long createdBy;
#JsonIgnore
#CreatedDate
private Long createdDate;
#JsonIgnore
#LastModifiedBy
private Long updatedBy;
#JsonIgnore
#LastModifiedDate
private Long updatedDate;
#JsonIgnore
#Version
private Integer version = 0;
}
and a Role class extends from GenericEntity like this:
#Getter
#Setter
#NoArgsConstructor
public class Role extends GenericEntity {
private String name;
private String desc;
private Integer sort;
}
And after that I have interface RoleRepo like this:
#Repository
public interface RoleRepo extends ReactiveCrudRepository<Role, Long>;
In Router function, I have 2 handler methods
private Mono<ServerResponse> findAllHandler(ServerRequest request) {
return ok()
.contentType(MediaType.APPLICATION_JSON)
.body(roleRepo.findAll(), Role.class);
}
private Mono<ServerResponse> saveOrUpdateHandler(ServerRequest request) {
return ok()
.contentType(MediaType.APPLICATION_JSON_UTF8)
.body(request.bodyToMono(Role.class).flatMap(role -> {
return roleRepo.save(role);
}), Role.class);
}
The method findAllHandler works fine, but the saveOrUpdateHandler throw exception like this:
java.lang.IllegalStateException: Required identifier property not found for class org.sky.entity.system.Role!
at org.springframework.data.mapping.PersistentEntity.getRequiredIdProperty(PersistentEntity.java:105) ~[spring-data-commons-2.2.0.M2.jar:2.2.0.M2]
at org.springframework.data.r2dbc.function.convert.MappingR2dbcConverter.lambda$populateIdIfNecessary$0(MappingR2dbcConverter.java:85) ~[spring-data-r2dbc-1.0.0.M1.jar:1.0.0.M1]
But when I move
#Id
private Long id;
from GenericEntity class to Role class, the two methods work fine.
Are there any Annations #MappedSuperclass/JPA in Spring Reactive Data like that
I wish the id field in GenericEntity for all extends class
Thanks for your help
Sorry, my English so bad
I had a similar problem and after some search, I didn't find an answer to your question, so I test it by writing code and the answer is spring data R2DBC doesn't need #Mappedsuperclass. it aggregates Role class properties with Generic class properties and then inserts all into the role table without the need to use any annotation.