spring boot Cannot invoke Repository because Repository is null - java

public class UserList {
private String id;
private String email;
private String userType;
private String rolls;
private String partner;
private Integer customersLinked;
private String position;
private String status;
#Autowired
ICustomerRepository customerRepository;
public UserList (Users user){
this.id = user.getId();
this.email = user.getEmail();
this.userType = user.getUserType();
this.rolls = user.getRolls();
this.partner = user.getPartner();
List<Customer> customersLinked = customerRepository.findAllByLinkedUsersIn(user.getId());
this.customersLinked = 0;
this.position = user.getPosition();
this.status =user.getStatus();
}
//Getter and Setter
}
This class is used as a list in the frontEnd ,get specific data ,not send all the data
#RequestMapping(value = "usersLinked/{id}/{type}", method = RequestMethod.GET)
public Object getUsersLinkedById(#PathVariable("id") String id,#PathVariable("type") Integer type) {
List<String> users = null;
switch (type) {
case 0:
users = usersRepository.findAll().stream().map(m -> m.getId()).collect(Collectors.toList());
break;
}
//Add userList
List<UserList> userList = new ArrayList<>();
if(users != null)
{
users.forEach(userId ->
{
Optional<Users> user = this.usersRepository.findById(userId);
userList.add(new UserList(user.get()));
});
}
return userList;
}
}
As you can see from above I am calling al the data from the user repository and sending it the list
My customer repository
public interface ICustomerRepository extends MongoRepository<Customer, String> {
Customer findByBusinessInformation_businessName(String businessName);
List<Customer> findByBusinessInformation_partnerAssigned(String partnerAssigned);
#Query("{ 'LinkedUsers' : ?0 }")
Customer findByLinkedUsers(String id);
List<Customer> findAllByLinkedUsersIn(String id);
}
In the userList I get the error when I add the logic wityh the customerRepository ,without the repository there everything is working(Want to use the repository to get an array of customer and then get the size() of the array and add it to linkedCustomers). Am I missing sommething

You are trying to inject the field customerRepository using Autowired annotation, but your class is not injectable.
You can add an annotation #Repository on your class UserList
Or use constructor injection (better way to inject your beans)

You're probably missing the #repository annotation on top of your repository class.
Another unrelated word of advice:
In your controller you use findAll and filter in java to keep only the ids.
Then you go to the same repository and perform another query per user-id from above.
This is a causing you to create multiple database calls which are one of the most expensive operations you can do, when you already have all your data from the first single query...
Also if you're only looking at the bottom part of the function you don't event need a query per each user-id (when you have a list of user ids as input), you can create a query that uses the 'in' convention and pass a list of user-ids to create a single db call.

First of all I would get rid of #Autowired ICustomerRepository customerRepository; in UserList class. It doesn't belong there. The counting of linked customers should be executed in ICustomerRepository and the result to be passed into UserList via the constructor.
e.g.
public class UserList {
private String id;
private String email;
private String userType;
private String rolls;
private String partner;
private Long customersLinked; //better use Long instead of Integer
private String position;
private String status;
// constructor takes the number of linked customers as parameter
public UserList (Users user, Long customersLinked ) {
this.id = user.getId();
this.email = user.getEmail();
this.userType = user.getUserType();
this.rolls = user.getRolls();
this.partner = user.getPartner();
this.customersLinked = customersLinked;
this.position = user.getPosition();
this.status =user.getStatus();
}
//Getter and Setter
}
and then create the count query in ICustomerRepository
e.g.
public interface ICustomerRepository extends MongoRepository<Customer, String> {
//other methods
Long countByLinkedUsersIn(String id); //not so sure if this query works in mongo
}
and finally in your controller
Optional<Users> user = this.usersRepository.findById(userId);
Long count = this.usersRepository.countByLinkedUsersIn(userId);
userList.add(new UserList(user.get(), count));
P.S. I have a doubt for the query method: Long countByLinkedUsersIn(String id);. Usually when repository methods have "In" in their names, countByLinkedUsersIn, then it is expected as parameter a List and not a single user id. However if your previous method List<Customer> findAllByLinkedUsersIn(String id); worked for you, then this one should work too.

Related

Convert Java object list to entity list

I have multiple objects in my array using . If I then send this to my Spring Boot backend with axios and output the FormData beforehand, I get the following image. That fits. In the backend, however, I need this list of objects as an entity. In this case, of type List. Do I do that?
Frontend code:
let data = new FormData();
...
data.append("zugeordnet", JSON.stringify(personNamen));
await axios.post("/neuerEintrag", data,...)
React:
Backend:
#PostMapping("/neuerEintrag")
public String neuerEintrag(HttpServletRequest req,#RequestParam("zugeordnet") List<?> zugeordnet,..) {
List<User> userListe = (List<User>) zugeordnet;
for(User inListe : userListe) //ERROR here
{
System.out.println("USER :" + inListe);
}
...
}
java.lang.ClassCastException: class java.lang.String cannot be cast to class com.home.calendar.User.User
UPDATE
For completeness, here is the user entity and the complete method for a new entry.
#PostMapping("/neuerEintrag")
public String neuerEintrag(HttpServletRequest req, #RequestParam("beschreibung") String beschreibung,
#RequestParam("datum") Date datum, #RequestBody List<User> zugeordnet,
#RequestBody List<Freunde> kontaktAuswahl, #RequestParam("neuAlt") String neuAlt,
#RequestParam("kalenderId") int kalenderId) { }
The User Entity:
#Entity
public class User {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;
private String name;
#JsonIgnoreProperties("user")
#OneToMany(cascade = CascadeType.ALL, orphanRemoval = true, mappedBy = "user")
private List<Kalender> kalenderEinträge;
public User() {
super();
// TODO Auto-generated constructor stub
}
public User(String name, List<Kalender> kalenderEinträge) {
super();
this.name = name;
this.kalenderEinträge = kalenderEinträge;
}
public List<Kalender> getKalenderEinträge() {
return kalenderEinträge;
}
[getter/setter]
Spring can't parse an unknown object.
To get it work, I suggest a new class for the "request".
#Data // lombok - this generates getter/setters/equals/hashcode for you
public class NeuerEintragRequest {
private List<User> zugeordnet;
private String beschreibung;
private int kalendarId;
// and your others fields
}
The controller can now use very type-safe objects.
#PostMapping("/neuerEintrag")
public String neuerEintrag(#RequestBody NeuerEintragRequest request) {
for(User user : request.getUserlist()) {
// a logging framework is a lot better. Try to use log4j or slf4j.
log.info("USER: {}", user);
}
...
}
Typescript
Let axios handle the typing and serializing. See this tutorial: https://masteringjs.io/tutorials/axios/post-json
To post all the needed data, you can create a new object.
// no formdata - just send the object
const data = { zugeordnet: personNamen, kalendarId: 123, beschreibung: 'abc' };
await axios.post("/neuerEintrag", data);
You can also create a interface in typescript, but this is going to much for a stackoverflow-answer. Try to learn more about spring and typescript.
Based on question & comments ,
your front end call data.append("zugeordnet", JSON.stringify(personNamen)); is converting your object to List<String> instead of List<User>.
So you can transform this List<String> to List<User> in your postMapping:
#PostMapping("/neuerEintrag")
public String neuerEintrag(HttpServletRequest req,#RequestParam("zugeordnet") List<?> zugeordnet,..) {
ObjectMapper mapper=new ObjectMapper();
for(String str:zugeordnet){
System.out.println(mapper.readValue(str, User.class));
}
...
}

Using SQL-IN-clause in custom #Query in JPA-/CrudRepository with the list or set as passed parameter?

Hi Spring and Hibernate experts!
Can any one say if it is possible to use SQL IN-clause in custom #Query in CrudRepository while the Arraylist or set of strings is passed as parameter?
I am relatively new to Spring and do not quite figure out why I get the following Spring error:
"java.lang.IllegalArgumentException: Parameter value [d9a873ed-3f15-4af5-ab1b-9486017e5611] did not match expected type [IoTlite.model.Device (n/a)]"
In this post (JPQL IN clause: Java-Arrays (or Lists, Sets...)?) the subject is discussed pretty closely but I cannot make the suggested solution to work in my case with custom #Query.
My demo repository as part of the spring boot restful application is the following:
#Repository
public interface DeviceRepository extends JpaRepository<Device, Long> {
#Query("SELECT d FROM Device d WHERE d IN (:uuid)")
List<Device> fetchUuids(#Param("uuid") Set<String> uuid);
}
And the model-class is the following:
#Entity
#SequenceGenerator(sequenceName = "device_seq", name = "device_seq_gen", allocationSize = 1)
#JsonIgnoreProperties(ignoreUnknown = true)
public class Device implements Serializable {
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "device_seq_gen")
#JsonIgnore
private Integer id;
#Column(unique=true, length=36)
#NotNull
private String uuid = UUID.randomUUID().toString();
#Column(name="name")
private String name;
#JsonInclude(JsonInclude.Include.NON_NULL)
private String description;
#OneToMany(
mappedBy="device",
cascade = CascadeType.ALL,
orphanRemoval = true
)
private List<Sensor> sensors = new ArrayList<>();
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
#JsonIgnore
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getDeviceUuid() {
return uuid;
}
public void setDeviceUuid(String deviceUuid) {
this.uuid = deviceUuid;
}
public List<Sensor> getSensors() {
return sensors;
}
public void addSensor(Sensor sensor){
sensor.setDevice(this);
sensors.add(sensor);
}
}
An here is the relevant part of the service calling the fetchUuids-custom-method with set-list of strings as parameter (service naturally being called by the relevant restcontroller):
#Service
public class DeviceService implements IDeviceService {
#Autowired
private DeviceRepository deviceRepository;
...
#Override
public List<Device> listDevices(Set<String> clientIds) {
return deviceRepository.fetchUuids(clientIds);
}
...
}
Quick fix
You have WHERE d IN (:uuid) in the custom query. You cannot match d, which is an alias for Device entity with :uuid parameter, which is a collection of Strings.
WHERE d.uuid IN (:uuid) would fix the query - it matches a String with Strings.
What you should do instead
It's rather misleading to name the method fetchUuids and return a list of Device instances. It's also unnecessary to write a custom query to do that. You can benefor from repository method name conventions and let Spring Data Jpa framework generate the query for you:
List<Device> findByUuidIn(Set<String> uuids);
You can write in this way
#Query(value = "select name from teams where name in :names", nativeQuery = true)
List<String> getNames(#Param("names") String[] names);
and call the function in service and pass an array of String as arguments.like this
String[] names = {"testing team","development team"};
List<String> teamtest = teamRepository.getNames(names);
Yes is possible to using collection in JPA query parameters.
Your query is wrong, it should be like this:
#Query("SELECT d FROM Device d WHERE d.uuid IN :uuid")

Spring Data JPA Unable to locate Attribute with the given name

I was trying to use Spring Data JPA on Spring Boot and I kept getting error, I can't figure out what the problem is:
Unable to locate Attribute with the the given name [firstName] on
this ManagedType [com.example.h2demo.domain.Subscriber]
FirstName is declared in my entity class. I have used a service class with DAO before with different project and worked perfectly.
My Entity class (getters and setters are also in the class) :
#Entity
public class Subscriber {
#Id #GeneratedValue
private long id;
private String FirstName,LastName,Email;
public Subscriber(long id, String firstName, String lastName, String email) {
this.id = id;
this.FirstName = firstName;
this.LastName = lastName;
this.Email = email;
}
}
...
My Repository Class
#Component
public interface SubscriberRepository extends JpaRepository<Subscriber,Long> {
Subscriber findByFirstName(String FirstName);
Subscriber deleteAllByFirstName(String FirstName);
}
My Service Class
#Service
public class SubscriberService {
#Autowired
private SubscriberRepository subscriberRepository;
public Subscriber findByFirstName(String name){
return subscriberRepository.findByFirstName(name);
}
public Subscriber deleteAllByFirstName(String name){
return subscriberRepository.deleteAllByFirstName(name);
}
public void addSubscriber(Subscriber student) {
subscriberRepository.save(student);
}
}
And My Controller class:
#RestController
#RequestMapping("/subscribers")
public class SubscriberController {
#Autowired
private SubscriberService subscriberService;
#GetMapping(value = "/{name}")
public Subscriber findByFirstName(#PathVariable("name") String fname){
return subscriberService.findByFirstName(fname);
}
#PostMapping( value = "/add")
public String insertStudent(#RequestBody final Subscriber subscriber){
subscriberService.addSubscriber(subscriber);
return "Done";
}
}
Try changing private String FirstName,LastName,Email; to private String firstName,lastName,email;
It should work.
findByFirstName in SubscriberRepository tries to find a field firstName by convention which is not there.
Further reference on how properties inside the entities are traversed https://docs.spring.io/spring-data/jpa/docs/current/reference/html/#repositories.query-methods.query-property-expressions
The same problem was when i had deal with Spring Data Specifications (https://www.baeldung.com/rest-api-search-language-spring-data-specifications)
Initial piece of code was:
private Specification<Project> checkCriteriaByProjectNumberLike(projectNumber: String) {
(root, query, criteriaBuilder) -> criteriaBuilder.like(root.get("project_number"), "%" + projectNumber)
}
The problem was in root.get("project_number"). Inside the method, I had to put the field name as in the model (projectNumber), but I sent the field name as in the database (project_number).
That is, the final correct decision was:
private Specification<Project> checkCriteriaByProjectNumberLike(projectNumber: String) {
(root, query, criteriaBuilder) -> criteriaBuilder.like(root.get("projectNumber"), "%" + projectNumber)
}
After I change my entity class variables from capital letter to small letter for instance Username to username the method Users findByUsername(String username); is working for me now .
As per specification , the property names should start with small case.
...The resolution algorithm starts with interpreting the entire part (AddressZipCode) as the property and checks the domain class for a property with that name (uncapitalized)....
It will try to find a property with uncapitalized name. So use firstName instead of FristName and etc..

How to get column names in result set in Spring data JPA

I have simple procedure which lists out users. I am using #NamedStoredProcedureQueries for procedure declaration and used EntityManager.createNamedStoredProcedureQuery for StoredProcedureQuery.
It returns the result properly but I need column name so that I will know which value is for which column.
My code goes something like this
Entity Class
#Entity
#NamedStoredProcedureQueries({ #NamedStoredProcedureQuery(name =
"sGetUserList", procedureName = "sGetUserList", parameters = {
#StoredProcedureParameter(mode = ParameterMode.IN, name = "user_id", type =
Integer.class) })
})
public class User {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Integer id;
private String name;
private String email;
//getters and setters
}
Custom Repositoty
public interface UserRepositoryCustom {
List<?> testProc() ;
}
Repository
public interface UserRepository extends JpaRepository<User, Long>,
UserRepositoryCustom{
}
Repository Implementation
public class UserRepositoryImpl implements UserRepositoryCustom{
#PersistenceContext
EntityManager em;
public List<Object> testProc() {
StoredProcedureQuery q = em.createNamedStoredProcedureQuery("sGetUserList");
q.setParameter("user_id", 1);
List<Object> res = q.getResultList();
return res;
}
}
I need result with column names.
You can get the column names along with their values in a Map. i.e Map<'column-name', value>.
Query query = entityManager.createNativeQuery("{call <<Your procedure>>}");
NativeQueryImpl nativeQuery = (NativeQueryImpl) query;
nativeQuery.setResultTransformer(AliasToEntityMapResultTransformer.INSTANCE);
List<Map<String,Object>> result = nativeQuery.getResultList();
This will be very helpful in a places where you want to use column names as a placeholder in HTML where value will replace it in runtime.
Here , I have written a method from you can get JSON from you can get key value pair of column and value
#Transactional
#Component
public class CustomRepository<T> {
#Autowired
private EntityManager em;
private ObjectMapper mapper = new ObjectMapper();
public List<T> getResultOfQuery(String argQueryString,Class<T> valueType) {
try {
Query query = em.createNativeQuery(argQueryString);
NativeQueryImpl nativeQuery = (NativeQueryImpl) query;
nativeQuery.setResultTransformer(AliasToEntityMapResultTransformer.INSTANCE);
List<Map<String,Object>> result = nativeQuery.getResultList();
List<T> resultList = result.stream()
.map(o -> {
try {
return mapper.readValue(mapper.writeValueAsString(o),valueType);
} catch (Exception e) {
ApplicationLogger.logger.error(e.getMessage(),e);
}
return null;
}).collect(Collectors.toList());
return resultList;
} catch (Exception ex) {
ApplicationLogger.logger.error(ex.getMessage(),ex);
throw ex;
}
}
}
The Only condition is that your query and pojo attribute name should be same
I'm not sure I understand what you are trying to do here. If you want to get all the users using Spring data you shouldn't be implementing your UserRepository. Spring Data does this for you.
In fact the JpaRepository already has the method you need.
List<User> findAll();
You can just call this to get a list of all your users and won't need to worry about the column names.
Just inject your repository where you need it and call the method to get all users:
#Autowire
UserRepository userRepository;
List<Users> allUsers = userRepository.findAll();
EDIT: If there is a particular reason you want to use stored procedures though there is a Spring Data way of doing this without implementing UserRepository yourself. You can do this by defining the following method:
public interface UserRepository extends JpaRepository<User, Long>{
#Procedure(name = "sGetUserList")
List<User> sGetUserList(#Param("user_id") Integer userId);
}
Again there shouldn't be any issue with resolving column names with this method.

Override Pageable findAll for selecting fewer columns in Spring Data Rest

How to Override spring data repository to select only selected columns when going to pages that are discovered from /api page in spring data rest.
I added findAll as below -
public interface UserRepository extends BaseRepository<User, Integer>, UserRepositoryCustom {
#Query("select u from User u where email = :email and password = :password")
#Cacheable(value = "user-cache", key = "#user.login")
#RestResource(exported = false)
public User findUserByEmailAndPassword(#Param("email") String email, #Param("password") String password);
#RestResource(rel = "byEmail", path = "byEmail")
public User findUserByEmail(#Param("email") String email);
#RestResource(rel = "byPhone", path = "byPhone")
public User findUserByPhone(#Param("phone") String phone);
#Override
#Query("select u.id,u.email,u.phone from User u ")
public Page<User> findAll(Pageable pageable);
}
/api/users is giving an error -
{"cause":null,"message":"PersistentEntity must not be null!"}
I created a UserSummaryProjection class in same package as User
#Projection(name = "summary", types = User.class)
public interface UserSummaryProjection {
Integer getId();
String getEmail();
}
Then, going at /api/users or /users/3?projection=summary gives me desired result without changing the Repository.
Selecting subelements of User and still creating a User is somewhat counterintuitive.
I would create another entity for example UserDetails, that will be mapped by the same table with the same mapping.
public class UserDetails {
private int uid;
private String email;
private String phone;
}
And create a Repository, based on this new Entity.

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