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How to correctly join tables in Spring Boot

I have a User, and the user has Expenses. In expenses table I want to have the expense id, the user who made the expense and the amount of expense. In the user table I want user id, his username, his current balance and list of all expenses he's made.
I want to join those 2, but I don't know how to correctly reference user, therefore user form Expense class is always null.
First, I send post request to create a user:
{
"username":"abcd",
"balance":"100"
}
then I want to create an expense, but here I'm not sure how to correctly send a User:
{
"username":"abcd",
"id":"1",
"balance":"100",
"amount":"20"
}
and this doesn't work, then I tried like this:
{
"User":{
"username":"abcd",
"id":"1",
"balance":"100"
},
"amount":"20"
}
and that didn't work either.
This is the User class:
#Entity
#Table(name = "Users")
public class User {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#NotBlank(message = "Username is mandatory")
private String username;
private Double balance = 0.0;
#OneToMany(mappedBy = "user")
private List<Expense> expenses;
...
I removed getters and setters from here.
Here is the Expense class:
#Entity
#Table(name = "Expenses")
public class Expense {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#ManyToOne
#JoinColumn(name = "user_id")
private User user;
private Double amount;
...
For saving the expense I use .save() from JpaRepository<Expense, Long> and for retrieveing everyting I use .findAll().
The result is always the same: get for all expenses gives
{
"id": 1,
"user": null,
"amount": 20
}
and get for all users gives
{
"id": 1,
"username": "abcd",
"balance": 100,
"expenses": []
}
Now I'm not sure whether I'm sending the requests the wrong way or joining the tables the wrong way or both.
EDIT: here is ExpenseController:
#RestController
public class ExpenseController {
#Autowired
IExpenseService expenseService;
#GetMapping("/expenses")
public List<Expense> findExpenses() {
return expenseService.findAll();
}
#PostMapping("/expenses")
public void createNewExpense(#RequestBody Expense expense) {
expenseService.createNewExpense(expense);
}
}
createNewUser(...) from ExpenseService
#Override
public void createNewExpense(Expense expense) {
repository.save(expense);
}
and ExpenseRepository:
#Repository
public interface ExpenseRepository extends JpaRepository<Expense, Long> {
}
UserController:
#RestController
public class UserController {
#Autowired
IUserService userService;
#GetMapping("/users")
public List<User> findUsers() {
return userService.findAll();
}
#GetMapping("/users/{id}")
public User findUserById(#PathVariable Long id) {
return userService.findById(id);
}
#PostMapping("/users")
public ResponseEntity<Object> createUser(#RequestBody User user) {
if (userService.checkIfUsernameIsTaken(user)) {
Map<String, Object> response = new HashMap<>();
response.put("status", HttpStatus.NOT_ACCEPTABLE);
response.put("errors", "Username is already taken");
response.put("timestamp", new Date());
return new ResponseEntity<>(response, HttpStatus.BAD_REQUEST);
} else {
userService.createNewUser(user);
User currentUser = userService.findById(userService.findByUsername(user.getUsername()));
Map<String, Object> response = new HashMap<>();
response.put("id", currentUser.getId());
response.put("username", currentUser.getUsername());
response.put("balance", currentUser.getBalance());
response.put("expenses", currentUser.getExpenses());
return new ResponseEntity<>(response, HttpStatus.OK);
}
}
#DeleteMapping("/users/{id}")
public void deleteUser(#PathVariable Long id) {
userService.deleteUser(id);
}
#PutMapping("/users/{id}/{balance}")
public void updateBalance(#PathVariable Long id, #PathVariable Double balance) {
userService.updateBalance(id, balance);
}
}
the rest of the User model is the same as the Expense model.

Try to send post request with this payload (field 'user' begins with a small letter), and i think the 'id' field in user object should be enough
{
"user":{
"username":"abcd",
"id":"1",
"balance":"100"
},
"amount":"20"
}
EDIT: Also you need to add #JsonIgnoreProperties("expenses") to your Expense entity to prevent jackson from recursive reading json
#Entity
#Table(name = "Expenses")
public class Expense {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#JsonIgnoreProperties("expenses")
#ManyToOne
#JoinColumn(name = "user_id")
private User user;
private Double amount;
.....

findRecord in Google CloudDatastore with Objectify

I want to use Objectify to query Google Cloud Datastore. What is an appropriate way to find a record based on a known key-value pair? The record is in the database, I verified this by Google's Datastore viewer.
Here is my method stub, which triggers the NotFoundException:
#ApiMethod(name="getUser")
public User getUser() throws NotFoundException {
String filterKey = "googleId";
String filterVal = "jochen.bauer#gmail.com";
User user = OfyService.ofy().load().type(User.class).filter(filterKey, filterVal).first().now();
if (user == null) {
throw new NotFoundException("User Record does not exist");
}
return user;
}
Here is the User class:
#Entity
public class User {
#Id
Long id;
private HealthVault healthVault;
private String googleId;
public User(String googleId){
this.googleId = googleId;
this.healthVault = new HealthVault();
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public HealthVault getHealthVault() {
return healthVault;
}
public void setHealthVault(HealthVault healthVault) {
this.healthVault = healthVault;
}
public String getGoogleId() {
return googleId;
}
public void setGoogleId(String googleId) {
this.googleId = googleId;
}
}

I think it fails because of transaction. You need to make a transctionless call like:
User user = OfyService.ofy().transactionless().load().type(User.class).filter(filterKey, filterVal).first().now();
More info about transactions on App Engine:
https://cloud.google.com/appengine/docs/java/datastore/transactions
https://github.com/objectify/objectify/wiki/Transactions
EDIT
Your object needs #Index annotation. It will add field to datastore index. Only properties that are in the index can be searchable. Filter method is one of them.
#Id
Long id;
#Index
private HealthVault healthVault;
#Index
private String googleId;
P.S. delete your object with googleId jochen.bauer#gmail.com and write it again to database after you updated your entity. And objectify will find it.

First add #Index in your fields model. I didn't see filterVal as an email in your model. Even so, to get the entity based in your filterVal assuming that is googleId is the field of your entity.
User user = OfyService.ofy().load().type(User.class).filter("googleId", filterVal).now();
And so if your filterKey is the id of your entity.
User user = OfyService.ofy().load().key(Key.create(User.class, filterKey)).now();

How to delete record in MongoDB using Spring Data

I want to delete an record based on Id in Spring.
but in database id value is object
EX:-
id: Object(34562341112313)
How to delete this record in Spring?

You do like this:
public void deleteRecord() {
MongoOperations mongoOperation = (MongoOperations) ctx.getBean("mongoTemplate");
Query searchQuery = new Query(Criteria.where("id").is(34562341112313));
mongoOperation.remove(searchQuery, Your_entity_class.class);
logger.info("Delete success");
}
This is my realistic example:
/**
* Delete by condition(s).
*/
public void deleteJob() {
MongoOperations mongoOperation = (MongoOperations) ctx.getBean("mongoTemplate");
Query searchQuery = new Query(Criteria.where("company").is("DCV"));
mongoOperation.remove(searchQuery, Job.class);
logger.info("Đã xóa các công việc đăng bởi DCV.");
}
Source: https://github.com/SmartJobVN/MongoDB_SpringDataMongo/blob/master/src/main/java/vn/smartJob/jobs/MongoSpringJavaConfigApplication.java#L132
Reference: http://docs.spring.io/spring-data/mongodb/docs/current/reference/html/

You should delete it like this:
#Repository
public class AppDaoClass{
#Autowired
MongoTemplate mongoTemplate;
#Override
public void deleteSomething(String somethingId) {
mongoTemplate.remove(Query.query(Criteria.where("somethingId").is(somethingId)), Ticket.class);
}
}
The first "somethingId" is the name you gave it in your model, and the second somethingId is for the Parametar you are giving in you method.
And your Domain Model:
#Document
public class Model {
#Id
private String somethingId;
private String someName;
private String someOtherName;
}
Be sure to user proper annotations for your classes #Document and #Repository. And add an #Id annotation to your ID field.
Hope this helps.

This is the way you can delete records in spring data mongoDB using MongoTemplate
WriteResult writeResult=mongoTemplate.remove(query,"collection_name");
OR
WriteResult writeResult=mongoTemplate.remove(query,EntityClassName.class);
You can also use repository Pattern
#Document(collection = "user")
public class User {
#Id
private String id;
private String username;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
}
#Repository
public interface UserRepository extend MongoRepository<User, String>{
public void delete(String id);
public void delete(User user);
public void deleteByUsername(String username);
}
you can use these method anywhere to delete records also u can write your custom methods

#Query(value = "{'_id' : ?0}", delete = true)
void deleteById(String id);

Can't remove entity with JPA

I'm trying to remove an entity from memory (at the moment I don't use DB) with JPA, when I use remove and then try to find the deleted entity it shows null, but when I use findAll method it retrieve all data (with removed entity)...
Profile.java
#Entity
#Table(name = "profile")
public class Profile {
#Id
#GeneratedValue
private Long id;
private String nombre;
private Boolean restrictedAccess;
private Boolean canValidate;
// private Set<AccessField> accessFields = new HashSet<AccessField>();
// private Set<AccessEntity> accessEntities = new HashSet<AccessEntity>();
#OneToMany(mappedBy = "profile", fetch = FetchType.EAGER)
private Set<AccessMenu> menuSections = new HashSet<AccessMenu>();
#OneToMany(mappedBy = "profile", fetch = FetchType.EAGER)
private Set<User> users = new HashSet<User>();
[getters and setters]
ProfileRepository
#Repository
#Transactional
public class ProfileRepository {
#PersistenceContext
private EntityManager entityManager;
public Profile save(Profile p) {
p = this.entityManager.merge(p);
this.entityManager.flush();
return p;
}
public void delete(Long id){
Profile profile = this.entityManager.find(Profile.class, id);
this.entityManager.remove(profile);
}
public List<Profile> findAll() {
CriteriaQuery cq = this.entityManager.getCriteriaBuilder().createQuery();
cq.select(cq.from(Profile.class));
return (List<Profile>) this.entityManager.createQuery(cq).getResultList();
}
public Profile findById(Long id){
return this.entityManager.find(Profile.class, id);
}
}
Controller method
#RequestMapping(value="profile/delete/{idProfile}", method = RequestMethod.GET)
public String delete(#PathVariable String idProfile,RedirectAttributes ra, Model model){
profileRepo.delete(Long.valueOf(idProfile));
model.addAttribute("profiles", profileRepo.findAll());
return "profile/list";
}

if you are are trying to delete an entity by using Id in the controller, do it like profileRepo.deleteById(Long.valueOf(idProfile));
this, not like this profileRepo.delete(profileRepo.findById(Long.valueOf(idProfile)));
Also use your repository functions like these,
public void deleteArtistById(Long artistId) {
Artist artist = manager.find(Artist.class, artistId);
if (artist != null) {
manager.getTransaction().begin();
manager.remove(artist);
manager.getTransaction().commit();
}
}
public void deleteArtist(Artist artist) {
manager.getTransaction().begin();
manager.remove(artist);
manager.getTransaction().commit();
}
You can take a look at this link for more detail:
http://kodejava.org/how-do-i-delete-entity-object-in-jpa/

At last I found a solution, the problem was when I tried to remove Profile, users and menuSections have related data, so finally I put in menuSections a cascade = CascadeType.REMOVE and in users set profile property to null

How to pass userid from one table to another table in spring mvc using hibernate

I'm using Spring security for the login. I have the User.java which contains user-details.
#Entity(name = "user_table")
//#Table(name = "user_table")
public class User {
#Id
#Column(name = "id")
private String userId;
#Column(name = "email" ,unique = true)
private String userEmail;
#Column(name = "password")
private String userPassword;
//getter and setters
}
I'm getting the whole data of the current user from the table by using spring security. This is the code:
public User findUserByEmail(String email) {
List<User> users = new ArrayList<User>();
try{
users = sessionFactory.getCurrentSession().createQuery("from user_table where email= ?").setParameter(0, email).list();
System.out.println("user is " +users);
}catch(Exception e){
System.out.println(e.getMessage());
e.printStackTrace();
}
if (users.size() > 0) {
return users.get(0);
} else {
return null;
}
}
#Override
public User getCurrentUser() {
Authentication auth = SecurityContextHolder.getContext()
.getAuthentication();
User currentUser = new User();
if (!(auth instanceof AnonymousAuthenticationToken)) {
UserDetails userDetails = (UserDetails) auth.getPrincipal();
System.out.println("User has authorities: "
+ userDetails.getAuthorities());
System.out.println("USERNAME:: "+userDetails.getUsername());
currentUser = findUserByEmail(userDetails
.getUsername());
System.out.println("currentUser "+currentUser);
System.out.println("currentUser "+currentUser.getUserId());
return currentUser;
}
return null;
}
What I want is to send the user id which I'm getting from currentUser.getUserId() to some other method. In that method I'm mapping to some other table like user_detail table where id is primary key. By sending id, I will get the other user_details which are not present in the user_table.
This is my UserDetail:
#Entity(name = "user_detail")
#Table(name = "user_detail")
public class UserDetail {
#Id
#GeneratedValue
#Column(name = "id")
private String userId;
//some other details like Address .
//getter and setter.
}
From controller I'm calling the above method like this:
UserService userService = new UserService();
User user=userDao.getCurrentUser();
String userId = user.getUserId();
System.out.println(userId);
UserDetail u=userDao.findUserById(userId);
and this is the method where I pass the current user id :
public UserDetail findUserById(String id) {
// TODO Auto-generated method stub
List<String> users = new ArrayList<String>();
try{
users = sessionFactory.getCurrentSession().createQuery("from user_detail where id= ?").setParameter(0, id).list();
System.out.println("user is " +users);
}catch(Exception e){
System.out.println(e.getMessage());
e.printStackTrace();
}
if (users.size() > 0) {
return null;
} else {
return null;
}
}
Now the result I'm getting here is null . Like user is null. What I'm doing wrong here?

There are several problems in your code. Just to point out some of them:
UserService userService = new UserService(); - you're manually creating the service object and not letting Spring-MVC injecting it into your controller, i.e. :
#Autowired
private UserService userService ;
UserDAO should be injected in your service, and not called from your controller :
class UserServiceImpl implements UserService{
#Autowired
private UserDAO userDAO;
}
All operations from your controller should call services methods and not DAO's methods. The service should use the DAO for database access. i.e.
UserDetail u=userDao.findUserById(userId);
should become
UserDetail u = userService.findUserById(userId);
and in your service :
class UserServiceImpl implements UserService{
#Autowire
private UserDAO userDAO;
#Override
public UserDetail findUserById(Long userId){
return userDAO.findUserById(userId);
}
}
if (users.size() > 0) {
return null;
} else {
return null;
}
is always returning null. Should be :
if (`users.isEmpty()){
return users.get(0);
}else { return null;}
users = sessionFactory.getCurrentSession().createQuery("from user_detail where id= ?").setParameter(0, id).list();
Your query is wrong. You should use your current bean class name and not the table name in your query, i.e. createQuery("FROM UserDetail WHERE id = ?")