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How do I populate two fields of entity using Hibernate?

I am building an API to return two fields as such:
{
currentPoints: 325,
badgeName: "Some Badge"
}
However, I am having trouble using hibernate in order populate those two fields. I made two attempts and both are throwing errors. Both of these errors can be found in their respective Repository file. In the 2nd attempt, I am using native=true and am able to get it to work using a SELECT *. However, I am trying to only populate and return two fields of the entity.
One solution I thought about is using the 2nd approach with a SELECT * and creating another package named response with CurrentInfoResponse class and just returning that class. However, I wanted to see if there was a way to avoid this using the current model that I have.
Possible Solution:
#Getter
#AllArgsConstructor
public class CurrentInfoResponse{
private Integer currentPoints;
private String badgeName
}
Package Structure:
Controller.java:
#GetMapping("/current-badge/{userId}")
public CurrentBadgeInfoModel getCurrentBadge(#PathVariable Integer userId){
return currentBadgeInfoService.getCurrentBadge(userId);
}
ServiceImpl.java:
#Override
public CurrentBadgeInfoModel getCurrentBadge(Integer userId){
return currentBadgeInfoRepository.getCurrentBadge(userId);
}
CurrentBadgeInfoModel.java:
#Getter
#Entity
#Table(name = "user_current_badge_info")
public class CurrentBadgeInfoModel {
#Id
#Column(name = "user_current_info_id")
private Integer userCurrentBadgeInfo;
#Column(name = "user_id")
private Integer userId;
#Column(name = "current_points")
private Integer currentPoints;
#ManyToOne
#JoinColumn(name = "badge_id")
private BadgeModel badgeModel;
}
BadgeModel.java
#Getter
#Entity
#Table(name = "badge_info")
public class BadgeModel {
#Id
#JoinColumn(name= "badge_id")
private Integer badgeId;
#Column(name = "badge_name")
private String badgeName;
}
Repository.java - ATTEMPT 1:
#Repository
public interface CurrentBadgeInfoRepository extends JpaRepository<CurrentBadgeInfoModel, Integer> {
#Query("SELECT cbim.currentPoints, cbim.badgeModel.badgeName FROM CurrentBadgeInfoModel cbim JOIN
cbim.badgeModel WHERE cbim.userId=?1")
CurrentBadgeInfoModel getCurrentBadge(Integer userId);
}
//Error: No converter found capable of converting from type [java.lang.Integer] to type [com.timelogger.model.CurrentBadgeInfoModel]
Repository.java - ATTEMPT 2:
#Repository
public interface CurrentBadgeInfoRepository extends JpaRepository<CurrentBadgeInfoModel, Integer> {
#Query(value = "SELECT current_points, badge_name FROM user_current_badge_info ucbi JOIN badge_info bi ON ucbi.badge_id=bi.badge_id WHERE user_id=?1", nativeQuery = true)
CurrentBadgeInfoModel getCurrentBadge(Integer userId);
}
//Error: Column 'user_current_info_id' not found

Using the SELECT clause of HQL should help you here.
If you don't have that constructor, you can add it
#Query("SELECT new CurrentBadgeInfoModel(cbim.currentPoints, cbim.badgeModel.badgeName) FROM CurrentBadgeInfoModel cbim JOIN
cbim.badgeModel WHERE cbim.userId=?1")
Notice the usage of new CurrentBadgeInfoModel(cbim.currentPoints, cbim.badgeModel.badgeName)

I think this is a perfect use case for Blaze-Persistence Entity Views.
I created the library to allow easy mapping between JPA models and custom interface or abstract class defined models, something like Spring Data Projections on steroids. The idea is that you define your target structure(domain model) the way you like and map attributes(getters) via JPQL expressions to the entity model.
A DTO model for your use case could look like the following with Blaze-Persistence Entity-Views:
#EntityView(CurrentBadgeInfoModel.class)
public interface CurrentInfoResponse {
Integer getCurrentPoints();
#Mapping("badgeModel.badgeName")
String getBadgeName();
}
The Spring Data integration allows you to use it almost like Spring Data Projections: https://persistence.blazebit.com/documentation/entity-view/manual/en_US/index.html#spring-data-features
CurrentInfoResponse findByUserId(Integer userId);
The best part is, it will only fetch the state that is actually necessary!

ListJoin and multiselect with criteriaquery with Polymorphism

I was wondering if anyone knows the cause of the Exception being thrown? I have the following entities below. Is it because some Employees returned aren't DriverEmployees and thus do not have routes?
#Entity
public class Employee {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "id", nullable = false)
private Integer id;
private String name;
}
#Entity
public class DriverEmployee extends Employee {
#OneToMany(fetch = FetchType.LAZY)
private List<Routes> routes;
}
#Entity
public class Routes {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "id", nullable = false)
private Integer id;
private String name;
private String description;
}
CriteriaQuery<Tuple> criteria = criteriaBuilder.createQuery(Tuple.class);
Root<Employee> employee = criteria.from(Employee.class);
Root<DriverEmployee> driverEmployee = criteriaBuilder.treat(employee, DriverEmployee.class);
ListJoin<DriverEmployee, Routes> routes = driverEmployee.joinList("routes");
// Want routes to be returned as a list in the multiselect.
criteria.multiselect(employee.get("name").alias("name"), routes.alias("routes"));
TypedQuery<Tuple> query = em.createQuery(criteria);
query.getResultList().forEach((t) -> {
process(t.get("name", String.class));
processList(t.get("routes", List.class).size());
});
The error I'm receiving is below. Anyone know how I can get the following to run successfully?
Caused by: java.lang.IllegalStateException: No data type for node: org.hibernate.hql.internal.ast.tree.IdentNode
+-[IDENT] IdentNode: 'routes' {originalText=routes}

In this current example you have tuple which contains one object of DriverEmployee and one object of Routes (I recommend you to rename this entity to Route and set #Table(name = "routes"). According to JavaDoc of multiselect():
If the type of the criteria query is CriteriaQuery (i.e., a criteria query object created by either the createTupleQuery method or by passing a Tuple class argument to the createQuery method), a Tuple object corresponding to the arguments of the multiselect method, in the specified order, will be instantiated and returned for each row that results from the query execution.
So it means that you CAN'T make a Tuple like Tuple<DriverEmployee, List<Routes>>
The way how you can reach such behavior of your current query is to do it by yourself. For instance:
your method with criteria:
CriteriaQuery<Tuple> criteria = criteriaBuilder.createQuery(Tuple.class);
Root<Employee> employee = criteria.from(Employee.class);
Root<DriverEmployee> driverEmployee = criteriaBuilder.treat(employee, DriverEmployee.class);
ListJoin<DriverEmployee, Routes> routes = driverEmployee.joinList("routes");
criteria.multiselect(employee.get("name").alias("name"), routes.alias("routes"));
TypedQuery<Tuple> query = em.createQuery(criteria);
List<Tuple> resultList = query.getResultList();
Map<String, List<Routes>> resultMap = getMapFromResultList(resultList);
resultMap.entrySet().forEach((name, routesList) -> {
process(name);
processList(routesList);
});
and the method of obtaining the map:
private Map<String, List<Routes>> getMapFromResultList(List<Tuple> tuples) {
Map<String, List<Routes>> map = new HashMap<>();
tuples.forEach(tuple -> {
String name = tuple.get("name", String.class);
Routes routes = tuple.get("routes", Routes.class);
map.computeIfPresent(name, (key, value) -> {
value.add(routes);
return value;
});
map.computeIfAbsent(name, (key) -> {
List<Routes> routesList = new ArrayList<>();
routesList.add(routes);
return routesList;
});
});
return map;
}

I guess the Hibernate JPA Criteria implememtation doesn't support that. If you really want to use the JPA Criteria API to do this, you are probably out of luck. In JPQL/HQL you could model this like SELECT e.name, r FROM DriverEmployee e LEFT JOIN e.routes r. On top of that you have to extract the values like Andrew Kolesnyk mentioned.
However, this is is the perfect use case for Blaze-Persistence Entity Views.
Blaze-Persitence is a query builder on top of JPA which supports many of the advanced DBMS features on top of the JPA model. I created Entity Views on top of it to allow easy mapping between JPA models and custom interface defined models, something like Spring Data Projections on steroids. The idea is that you define your target structure the way you like and map attributes(getters) via JPQL expressions to the entity model. Since the attribute name is used as default mapping, you mostly don't need explicit mappings as 80% of the use cases is to have DTOs that are a subset of the entity model.
A mapping for your model could look as simple as the following
#EntityView(DriverEmployee.class)
interface EmployeeDto {
#IdMapping
Integer getId();
String getName();
List<RoutesDto> getRoutes();
}
#EntityView(Routes.class)
interface RoutesDto {
#IdMapping
Integer getId();
String getName();
}
Querying is a matter of applying the entity view to a query, the simplest being just a query by id.
EmployeeDto dto = entityViewManager.find(entityManager, EmployeeDto.class, id);
The Spring Data integration allows you to use it almost like Spring Data Projections: https://persistence.blazebit.com/documentation/entity-view/manual/en_US/index.html#spring-data-features and it can also be saved back. Here a sample repository
#Repository
interface EmployeeRepository {
EmployeeDto findOne(Long id);
}
It will only fetch the mappings that you tell it to fetch.
Here you can see an example project: https://github.com/Blazebit/blaze-persistence/tree/master/examples/spring-data-webmvc

Select only some columns from a table

Is there a way to select only some columns from a table using jpa?
My tables are huge and I am not allowed to map all the columns in my entities. I tried to create an entity (as a side note, I don't have PKs in my tables):
#Entity
#Table(name = "SuperCat")
#Getter
#Setter
public class Cat{
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE)
private Long id;
#Column(name="nameCat")
private String name;
}
and then in my repository to
public interface CatRepository extends
CrudRepository<Cat, Long> {
#Query(
"SELECT name FROM Cat")
Page<Cat> getAlCats(Pageable pageable);
This is only a simple example, but the idea is the same. I have searched a lot and I found projections, but there you need to map the whole table, then I found native queries, but still doesn't apply. I know I can return an Object and the other solution is to use query with NEW and create my own object (no #entity, like a pojo). But is there a way that I can do this using jpa, to be able to use repository and services, if I am creating my own pojo then i will create a #transactional class put the queries (with NEW) there and this is it. I don't like this approach and I don't think that the jpa does't allow you to select only some columns, but I didn't find a proper way.
Maybe you will ask what is the result if I am doing like this:
I get this error: "Cannot create TypedQuery for query with more than one return using requested result type [java.lang.Long]"
(For new queries, I am talking about : http://www.java2s.com/Tutorials/Java/JPA/4800__JPA_Query_new_Object.htm maybe I was not clear)

You can do the same by using below approach.
Just create a constructor in entity class with all the required parameters and then in jpa query use new operator in query like below.
String query = "SELECT NEW com.dt.es.CustomObject(p.uniquePID) FROM PatientRegistration AS p";
TypedQuery<CustomObject> typedQuery = entityManager().createQuery(query , CustomObject.class);
List<CustomObject> results = typedQuery.getResultList();
return results;
And CustomObject class should look like below with the constructor.
public class CustomObject {
private String uniquePID;
public CustomObject(String uniquePID) {
super();
this.uniquePID = uniquePID;
}
public String getUniquePID() {
return uniquePID;
}
public void setUniquePID(String uniquePID) {
this.uniquePID = uniquePID;
}
}

spring-data-jpa projection not need to map the whole table, just select the necessary fileds :
// define the dto interface
public interface CatDto {
String getName();
// other necessary fields
...
}
#Query(value = "select c.name as name, ... from Cat as c ...)
Page<CatDto> getAllCats(Pageable pageable);
By this way, CatDto is an interface and it only includes some fileds part of the whole table. Its fields name need to match the select field's alias name.

Spring JPA native query with Projection gives "ConverterNotFoundException"

I'm using Spring JPA and I need to have a native query. With that query, I need to get only two fields from the table, so I'm trying to use Projections. It isn't working, this is the error I'm getting:
org.springframework.core.convert.ConverterNotFoundException: No converter found capable of converting from type [org.springframework.data.jpa.repository.query.AbstractJpaQuery$TupleConverter$TupleBackedMap] to type [com.example.IdsOnly]
I tried to follow precisely the instructions of that page I linked, I tried to make my query non-native (do I actually need it to be native if I use projections, btw?), but I always get that error.
If I use an interface it works, but the results are proxies and I really need them to be "normal results" that I can turn into json.
So, here's my code. The Entity:
import lombok.Data;
import lombok.NoArgsConstructor;
#Data
#NoArgsConstructor
#Entity
#Table(name = "TestTable")
public class TestTable {
#Id
#Basic(optional = false)
#GeneratedValue(strategy = GenerationType.SEQUENCE)
#Column(name = "Id")
private Integer id;
#Column(name = "OtherId")
private String otherId;
#Column(name = "CreationDate")
#Temporal(TemporalType.TIMESTAMP)
private Date creationDate;
#Column(name = "Type")
private Integer type;
}
The class for the projection:
import lombok.Value;
#Value // This annotation fills in the "hashCode" and "equals" methods, plus the all-arguments constructor
public class IdsOnly {
private final Integer id;
private final String otherId;
}
The Repository:
public interface TestTableRepository extends JpaRepository<TestTable, Integer> {
#Query(value = "select Id, OtherId from TestTable where CreationDate > ?1 and Type in (?2)", nativeQuery = true)
public Collection<IdsOnly> findEntriesAfterDate(Date creationDate, List<Integer> types);
}
And the code that tries to get the data:
#Autowired
TestTableRepository ttRepo;
...
Date theDate = ...
List<Integer> theListOfTypes = ...
...
Collection<IdsOnly> results = ttRepo.findEntriesAfterDate(theDate, theListOfTypes);
Thanks for the help. I really don't understand what I'm doing wrong.

with spring data you can cut the middle-man and simply define
public interface IdsOnly {
Integer getId();
String getOtherId();
}
and use a native query like;
#Query(value = "Id, OtherId from TestTable where CreationDate > ?1 and Type in (?2)", nativeQuery = true)
public Collection<IdsOnly> findEntriesAfterDate(Date creationDate, List<Integer> types);
check out https://docs.spring.io/spring-data/jpa/docs/current/reference/html/#projections

The query should be using a constructor expression:
#Query("select new com.example.IdsOnly(t.id, t.otherId) from TestTable t where t.creationDate > ?1 and t.type in (?2)")
And i dont know Lombok, but make sure there is a constructor that takes the two IDs as parameters.

JPA 2.1 introduces an interesting ConstructorResult feature if you want to keep it native.

You can return list of Object Array (List) as return type of the native query method in repository class.
#Query(
value = "SELECT [type],sum([cost]),[currency] FROM [CostDetails] " +
"where product_id = ? group by [type],[currency] ",
nativeQuery = true
)
public List<Object[]> getCostDetailsByProduct(Long productId);
for(Object[] obj : objectList){
String type = (String) obj[0];
Double cost = (Double) obj[1];
String currency = (String) obj[2];
}

#Query(value = "select isler.saat_dilimi as SAAT, isler.deger as DEGER from isler where isler.id=:id", nativeQuery = true)
List<Period> getById(#Param("id") Long id);
public interface Period{
Long getDEGER();
Long getSAAT();
}
as seen in the example code for native query given above, cast return values to any value like as "SAAT", "DEGER" and then define interface "period" which have getDEGER() and getSAAT(). Even if I have not understand why parameter after get must be uppercase, in lowercase scenario it didn't work properly. ie. interface with getDeger(), getSaat() does not work properly in my case.

Spring Data REST making range check with QueryDSL binding

I have request like this:
http://localhost:4000/services/querywithdsl?min=30&max=90
My domain entity only consists of id :
#Entity
#Data
public class ServiceNumberPorting {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(updatable = false, nullable = false)
private Long id;
}
And my rest controller with predicate
#GetMapping(value = "/services/querywithdsl")
public ResponseEntity<List<ServiceNumberPortingMapper>>getServiceNumberPortingWithDsl(#QuerydslPredicate(root = ServiceNumberPorting.class) Predicate predicate) {
...
}
Repository:
public interface ServiceNumberPortingRepository extends JpaRepository<ServiceNumberPorting, Long>,QuerydslPredicateExecutor<ServiceNumberPorting>, QuerydslBinderCustomizer<QServiceNumberPorting>
I want to build query with querydsl like this one using bindings
..where id>min and id< max
All examples I found are directly mapping query parameters to entity column, but in this example, I have only id in my entity and I want to do range check with incoming parameter values which have different name than my entity columns.
However, since my domain won't consist of min and max columns I could't get it working with customizing binding such as using QueryDslBinderCustomizer:
bindings.bind(store.city).single((path, value) -> path.endsWith(value));
How to accomplish that?
Here is docs that I gone through:
spring data examples
binding examples

One of the solutions I can think of is this:
In your repository,I have defined a method getValueLyingBetween and written a simple query:
public interface ServiceNumberPortingRepository extends JpaRepository...{
#Query("SELECT m FROM <YOUR_TABLE_NAME> m where ( m.id >=:min and m.id <= :max )")
public ServiceNumberPorting getValueLyingBetween(#Param("min") String min, #Param("max") String max);
}
And then you can simply call this repository method from your controller with min and max values.
Is this what you were looking for?