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JPA createQuery where condition does not work

I am trying to use JPA to fetch records from database. However I am able to insert records indatabse and even get all the records using createQuery method of class EntityManager.
But in below case I am not getting why the condition in where clause is not working.
Please help me figure it out.
POJO class :
#Entity
#Table(name = "frameworks_filter")
public class FilteredFrameworksDbStructure {
#Id
#Column(name="id")
#GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;
#Column(name = "regular_name")
private String regularName;
#Column(name = "component_name")
private String componentName;
#Column(name = "component_owner")
private String componentOwner;
#Column(name = "frameworks")
private String frameworks;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getRegularName() {
return regularName;
}
public void setRegularName(String regularName) {
this.regularName = regularName;
}
public String getComponentName() {
return componentName;
}
public void setComponentName(String componentName) {
this.componentName = componentName;
}
public String getComponentOwner() {
return componentOwner;
}
public void setComponentOwner(String componentOwner) {
this.componentOwner = componentOwner;
}
public String getFrameworks() {
return frameworks;
}
public void setFrameworks(String frameworks) {
this.frameworks = frameworks;
}
}
DAO class method:
public List<FilteredFrameworksDbStructure> getFilteredFrameworks(String regularName) {
EntityManager entityManager = entityManagerFactory.createEntityManager();
List<FilteredFrameworksDbStructure> filteredFrameworksDbStructureList = entityManager
.createQuery("from FilteredFrameworksDbStructure F where F.regularName = :regular", FilteredFrameworksDbStructure.class)
.setParameter("regular", regularName)
.getResultList();
return filteredFrameworksDbStructureList;
}
Issue : Condition in where clause does not work. It simply fetch all the records irrespective of the regularName provided.
Regards,
Parag Vinchurkar

Why don't you use the JpaRepository or CrudRepository to fetch your results? Check out this tutorial here and here on how to use them.
And you can use your where clause. Please see below the example repository you can use to obtain the same results as the entityManager
public interface FilteredFrameworksDbStructureRepo extends JpaRepository<FilteredFrameworksDbStructure , Integer>{
List<FilteredFrameworksDbStructure> findAllByRegularName(String regularName)
}
Please note that you will have to change your id member variable from int to Integer

Criteria Builder and Jquery DataTables - Custom query

I'm using jquery Datatables together with Spring JPA.
I want to create a custom Query so that my Datatable will show a list of items based on the id of a ManyToOne related object.
PS. I have obviously declared Repositories, Mapper and Entities for these DTOs, I'm just avoiding to write all the classes because I find it useless.
public class SezioniDTO {
private static final long serialVersionUID = 1L;
private long id;
private LocalDate sezDtaggiornamento;
private Comune Comune;
}
public class Comune {
private static final long serialVersionUID = 1L;
private long id;
private String comCap;
private String comCodbelfiore;
private String comCodcomune;
}
These are my classes (i use mapstruct to map the dtos from the entities).
How can i use criteria builder inside my repository and services to search for Sezionis based on Comunes id?
I'm new to QueryDSL and Specifications, i just would like to obtain something like this:
#Query("Select * from Sezioni s WHERE s.id_Comune = :id", native="true")
public DataTablesOutput <Object> findByField (#Param(value="id", input);
This is the current Service Implementation
#Service
public class SezioniServiceImpl implements SezioniService{
#Autowired
SezioniRepository repo;
#Autowired
SezioniMapper mapper;
#Autowired
SezioniSpecifications sezSpec;
#Override
public List<SezioniDTO> findAll() {
return repo.findAll().stream().map(x -> mapper.entityToDto(x, new CycleAvoidingMappingContext()))
.collect(Collectors.toList());
}
#Override
public List<SezioniDTO> findByIdComune(Long idcom){
return repo.findSezionibyIdComune(idcom).stream().map(x -> mapper.entityToDto(x, new CycleAvoidingMappingContext()))
.collect(Collectors.toList());
}
#Override
public SezioniDTO save(SezioniDTO entity) {
return null;
}
#Override
public Optional<SezioniDTO> findById(Long id) {
// TODO Auto-generated method stub
return null;
}
#Override
public void delete(SezioniDTO entity) {
// TODO Auto-generated method stub
}
#Override
public void deleteById(Long id) {
// TODO Auto-generated method stub
}
#Override
public long count() {
// TODO Auto-generated method stub
return 0;
}
#Override
public DataTablesOutput<SezioniDTO> getSezioniTable(#Valid DataTablesInput input) {
return repo.findAll(input, null, null, a -> mapper.entityToDto(a, new CycleAvoidingMappingContext()) );
}
}
and the current Repository for SezioniDTO
#Repository
public interface SezioniRepository extends JpaRepository<Sezione,Long>, JpaSpecificationExecutor<Sezione>, DataTablesRepository<Sezione,Long> {
#Query(value = "SELECT * FROM db.sezione WHERE sez_com_prg = :id ORDER BY sez_numsezione", nativeQuery = true)
public List <Sezione> findSezionibyIdCom(#Param(value = "id") Long id);
}
Where Sezione is the current Entity. As you can see, it extends , and DataTablesOutput work only with Specifications, which I haven't understood at all.
I simply would like to create a method similar to the public List I have in the repo, but with a DataTablesOutput return instead.

Define Entities:
#Entity
public class Sezioni {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private LocalDate sezDtaggiornamento;
#OneToOne(cascade = {CascadeType.ALL})
#JoinColumn(name = "comune_id")
private Comune Comune;
// getters & setter are omitted
}
and
#Entity
public class Comune {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private String comCap;
private String comCodbelfiore;
private String comCodcomune;
// getters & setter are omitted
}
Define repository
#Repository
public interface SezioniRepository extends JpaRepository<Sezioni, Long> {
#Query("select s from Sezioni s where s.Comune.id = :id")
List<Sezioni> findByComuneId(Long id);
}
Use (here in test)
#DataJpaTest
class SezioniRepositoryTest {
#Autowired
SezioniRepository sezioniRepository;
#BeforeEach
void setUp() {
Comune comune = new Comune();
comune.setComCap("cap42");
comune.setComCodcomune("cod43");
Sezioni sezioni = new Sezioni();
sezioni.setComune(comune);
sezioni.setSezDtaggiornamento(LocalDate.of(1970, 1, 1));
sezioniRepository.save(sezioni);
}
#Test
void test() {
List<Sezioni> sezionis = sezioniRepository.findByComuneId(1L);
assertEquals(1, sezionis.size());
assertEquals("cap42",sezionis.get(0).getComune().getComCap());
}
}
Next you can use MapStruct to map entities into DTO (if you prefer to expose DTO on your API)

Criteria Builder's advantage is to build queries dynamically upon your business login needs:
Consider next example:
#Service
public class SezioniQuery {
#PersistenceContext
private EntityManager entityManager;
List<Sezioni> select(TriFunction<CriteriaBuilder, Root<Sezioni>, CriteriaQuery<Sezioni>, CriteriaQuery<Sezioni>> builder) {
CriteriaBuilder criteriaBuilder = entityManager.getCriteriaBuilder();
CriteriaQuery<Sezioni> query = criteriaBuilder.createQuery(Sezioni.class);
// SQL FROM clause
Root<Sezioni> from = query.from(Sezioni.class);
// SQL SELECT clause
CriteriaQuery<Sezioni> select = query.select(from);
// build WHERE somewhere later
CriteriaQuery<Sezioni> apply = builder.apply(criteriaBuilder, from, query);
// execute
TypedQuery<Sezioni> typedQuery = entityManager.createQuery(apply);
return typedQuery.getResultList();
}
}
^^ here we define boilerplate.
Next we can reuse it to build different queires:
// #BeforeEach void setUp() {...} omitted see prev. answer
#Test
void testEqual() {
Long id = 1L;
List<Sezioni> sezionis = sezioniQuery.select((cb, from, query) ->
// WHERE id=1
query.where(cb.equal(from.get("id"), id)));
assertEquals(1, sezionis.size());
assertEquals("cap42",sezionis.get(0).getComune().getComCap());
}
#Test
void testGreater() {
List<Sezioni> sezionis = sezioniQuery.select((cb, from, query) ->
// WHERE id > 0
query.where(cb.gt(from.get("id"), 0)));
assertEquals(1, sezionis.size());
assertEquals("cap42",sezionis.get(0).getComune().getComCap());
}
So, using CriteriaBuilder you can build queries dynamically but this requires a bit more code, non-type-safe code.
Whereas JpaRepository extension is type-safe but non-dynamiс

Java EE 8 initializing EntityManager during transaction

Im trying to build a simple web service, right now I only have 3 classes, an entity class, a DAO class and a tester class.
My entity class:
#Entity
#Table(name="sales")
public class Sale implements Serializable{
#Id
#Column(name = "idsale_id")
#GeneratedValue(strategy = GenerationType.IDENTITY)
private int idsale_id;
#Column(name = "grand_total", nullable = false)
private double grand_total;
public Sale() {
}
public Sale(double grand_total) {
this.grand_total = grand_total;
}
My Database Operations class
#ApplicationScoped
public class DatabaseOperations {
#PersistenceContext(unitName = "owlJPA")
EntityManager em;
#Transactional
public String createSale(double grand_total) {
Sale sale = new Sale(grand_total);
em.persist(sale);
em.flush();
return "Successfully added new entry in DB";
}
}
REST handling code
#RequestScoped
#Path("/hello-world")
public class HelloResource {
#Inject
DatabaseOperations databaseOperations;
#POST
#Produces("text/plain")
#Consumes(MediaType.APPLICATION_JSON)
public String POSTrecieved(JsonObject jsonRaw) {
DatabaseOperations databaseOperations = new DatabaseOperations();
try {
String tempStr = jsonRaw.getJsonObject("newSale").getString("grand_total");
double grand_total = Double.parseDouble(tempStr);
String x = databaseOperations.createSale(grand_total);
return "SUCESSFULLY ADDED NEW SALE, with grand total of: "+x;
}
catch(Exception error){
return error.toString();
}
}
Whenever I try and run a transaction by calling the createSale method, the sale object gets created just fine, but i get a nullPointerException error as my entityManager em is null. But shouldn't my entityManager em already be instantialized as i did #ApplicationScoped?

Hibernate: generated Id remains in a not persistent entity after SQLIntegrityConstraintViolationException

Hello, everybody!
Some time ago I run into a trouble: if save method of repository fails, identifier, injected to a bean by Hibernate, remains in the bean. That behaviour may led us to a situation, when we will think about our not persistent bean as about persistent one. I would be pleased to know what practice is common to avoid this situation.
Example test(spring boot + hibernate + oracle database):
#Entity
#SequenceGenerator(name = "TEST_ENTITY_GENERATOR", allocationSize = 1, sequenceName = "TEST_ENTITY_SEQ")
public class TestEntity {
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "TEST_ENTITY_GENERATOR")
private Long id;
#Column(nullable = false)
private String name;
public Long getId() {
return id;
}
}
#Repository
public interface TestEntityRepository extends JpaRepository<TestEntity, Long> {
}
#RunWith(SpringRunner.class)
#SpringBootTest
public class RemainingIdTest {
#Autowired
private TestEntityRepository testEntityRepository;
#Test
public void test() {
TestEntity entity = new TestEntity();
try {
Assertions.assertThat(entity.getId()).isNull();
testEntityRepository.save(entity);
Assertions.fail("Save must fail");
} catch (DataIntegrityViolationException e) {
Assertions.assertThat(entity.getId()).isNotNull();
}
}
}

A possible solution is to use org.hibernate.event.spi.PreInsertEventListener where we can bind the transaction with a processor that will clear your entity if transaction is failed.
Example:
#Component
public class IdentifierCleaner implements PreInsertEventListener {
#Autowired
private EntityManagerFactory entityManagerFactory;
#PostConstruct
private void init() {
SessionFactoryImpl sessionFactory = entityManagerFactory.unwrap(SessionFactoryImpl.class);
EventListenerRegistry registry = sessionFactory.getServiceRegistry().getService(EventListenerRegistry.class);
registry.getEventListenerGroup(EventType.PRE_INSERT).appendListener(this);
}
#Override
public boolean onPreInsert(PreInsertEvent event) {
Object entity = event.getEntity();
event.getSession().getActionQueue().registerProcess(((success, session) -> {
if (!success) {
event.getPersister().resetIdentifier(
entity,
event.getId(),
event.getPersister().getVersion(entity),
event.getSession()
);
}
}));
return false;
}
}

Why ResponseEntity calls hibernate while lazy loading active

Below is the DAO. I am getting the first UppeningUsers object. Note that here for this function I do not want to return peopleWhoBlockedMe set which is located inside the UppeningUsers..
But in different functions I would like to return that information. Note that Both of them are LAZY fetching. With evict I tried to detach the object but still it did not work.
First of all RESTcontroller is below. Then the DAO code is below. Then two entity descriptions are below.
Question is: I see that until
return new ResponseEntity(returned, HttpStatus.OK);
There is only one query which is the typical select. I do not want hibernate to go and take also UserBlock information of that specific UppeningUser. Because it is not needed for this service response. However even though it is lazy loading for some reason
return new ResponseEntity(returned, HttpStatus.OK);
calls the hibernate. I dont know why in restcontroller still it is connected to the database. I tried evict but didnt work.
The json response is
{"id":7,"peopleWhoBlockedMe":[{"blockedId":7}]}
But I do not want for this function to return this peopleWhoBlockedMe. It can be empty.
PLEASE NOTE that in other service for example I will explictly request this peopleWhoBlockedMe but just for this business logic I do not need this information. So what I can do to prevent this so whenever I actually want to call peopleWhoBlockedMe I can get it. Not automaticly.
#RestController
public class TempController {
#Autowired
UppeningUsersService uppeningUsersService;
#RequestMapping(value = "/testing", method = RequestMethod.GET)
public ResponseEntity<UppeningUsers> getPhotos() {
try {
UppeningUsers returned = uppeningUsersService.getUsersDetailsPartial();
return new ResponseEntity<UppeningUsers>(returned, HttpStatus.OK);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
}
This part is the DAO.
#Repository
public class UppeningUsersDAO {
#Autowired
private SessionFactory sessionFactory;
public void setSessionFactory(SessionFactory sf) {
this.sessionFactory = sf;
}
/**
* Get Existing user. Return error if there is not.
* #param incomingUser user who requested access.
* #return returns the guy information. All information.
*/
#Transactional
public UppeningUsers getUserDetails() throws Exception {
Session session = this.sessionFactory.getCurrentSession();
Query query = session.createQuery("from UppeningUsers ");
UppeningUsers returning = (UppeningUsers) query.list().get(0);
session.evict(returning);
return returning;
}
}
The main table is this one..
#Entity
#Table(name = "uppening_users")
#Proxy(lazy = true)
public class UppeningUsers {
#Id
#Column(name = "id")
#GeneratedValue(strategy = GenerationType.IDENTITY)
private
int id;
#OneToMany(mappedBy = "blockedId",cascade =CascadeType.ALL, fetch = FetchType.LAZY)
private Set<UserBlocks> peopleWhoBlockedMe;
public UppeningUsers() {
super();
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public Set<UserBlocks> getPeopleWhoBlockedMe() {
return peopleWhoBlockedMe;
}
public void setPeopleWhoBlockedMe(Set<UserBlocks> peopleWhoBlockedMes) {
this.peopleWhoBlockedMe = peopleWhoBlockedMes;
}
}
Now here is the other table.
#Entity
#Table(name="user_blocks")
#Proxy(lazy = true)
public class UserBlocks {
#Id
#Column(name="id")
#GeneratedValue(strategy= GenerationType.IDENTITY)
int id;
#Column(name = "blocked_id",insertable = false,updatable = false)
private int blockedId;
public int getBlockedId() {
return blockedId;
}
public void setBlockedId(int blockedId) {
this.blockedId = blockedId;
}
}
UPDATE: 2 forgot to add the service
#Service("uppeningUserService")
public class UppeningUsersService {
#Autowired
UppeningUsersDAO uppeningUsersDAO;
public UppeningUsers getUsersDetailsPartial( ) throws Exception {
return uppeningUsersDAO.getUserDetails();
}
}

Jens is right about her sentence. The layer methodology and writing business objects fix the issue. Thank you.