Persist Nested Entity Spring Rest Data - java

I have a User Class
#Entity(name = "users")
#Table(name = "users")
public class User implements UserDetails {
static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "user_id", nullable = false)
private Long id;
#Column(name = "username", nullable = false, unique = true)
private String username;
#Column(name = "password", nullable = false)
private String password;
}
Tied to a simple Repository
public interface UserRepository extends PagingAndSortingRepository<User, Long> {
}
And I have an Instructor Class that has a nested User object
#Entity
#Table(name = "instructors")
public class Instructor {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "instructor_id", nullable = false, updatable = false)
private Long id;
#OneToOne(fetch = FetchType.EAGER)
#JoinColumn(name = "user_id")
private User user;
#OneToMany(fetch = FetchType.EAGER)
#JoinColumn(name = "course_id")
private List<Course> courses;
}
It is saved with the following repository
public interface InstructorRepository extends PagingAndSortingRepository<Instructor, Long> {
}
The JSON I am posting
{
"user": {
"id": 1
}
}
When I try to do a POST to /instructors . User is coming in null. Is there something I am missing to get JPA to tie the two together? I have tried adding CascadeType.ALL onto the field and that only throws a detached persist exception.

Leave the CascadeType.ALL to Instructor like you already tried:
#ManyToOne(fetch = FetchType.EAGER, cascade=CascadeType.ALL)
#JoinColumn(name = "user_id")
private User user;
In addition add the following to User. Seems to work with me. It provides the mapping information and makes JPA treat User managed
#OneToMany(mappedBy="user")//, cascade=CascadeType.ALL)
private List<Instructor> instructors = new ArrayList<>();
I have commented out the cascadeType in the above but it might be useful if you want to persist User wit all of its Instructors.

Related

Got java "stackoverflow" when join two tables

I have two java entity classes :
#Table(name = "user")
public class UserEntity
{
#Id
#Column(name = "id", unique = true, nullable = false)
private Long id;
#OneToOne(cascade = CascadeType.PERSIST, fetch = FetchType.EAGER)
#JoinColumn(name = "opportunity_id")
private OpportunityEntity opportunity;
}
and
#Table(name = "opportunity")
public class OpportunityEntity
{
#Id
#Column(name = "id", unique = true, nullable = false)
private Long id;
#OneToMany
#JoinColumn(name = "opportunity_id")
private List<UserEntity> users;
#OneToOne
#JoinColumn(name = "mainuser_id")
private UserEntity mainUser;
}
When i search for a list of Users [find users], i've got a "stackoverflow" when mapping User.opportunity.
the bug was clear that the opportunity.mainUser refer to User which itself refer to the same opportunity.
Is there another way to design my models ?
For example create a boolean isMain in User Model ?
Try to specify relationship to UserEntity by adding mappedBy to annotatation
#Table(name = "opportunity")
public class OpportunityEntity
{
#Id
#Column(name = "id", unique = true, nullable = false)
private Long id;
#OneToMany
#JoinColumn(name = "opportunity_id")
private List<UserEntity> users;
#OneToOne(mappedBy="opportunity")
#JoinColumn(name = "mainuser_id")
private UserEntity mainUser;
}

Spring Boot - combine nested resources for single API calls

Suppose you have two resources, User and Account. They are stored in separate tables but have a one-to-one relationship, and all API calls should work with them both together. For example a POST request to create a User with an Account would send this data:
{ "name" : "Joe Bloggs", "account" : { "title" : "My Account" }}
to /users rather than have multiple controllers with separate routes like users/1/account. This is because I need the User object to be just one, regardless of how it is stored internally.
Let's say I create these Entity classes
#Table(name = "user")
public class User {
#OneToOne(mappedBy = "user", cascade = CascadeType.ALL, orphanRemoval = true, fetch = FetchType.LAZY)
#NotNull
Account account;
#Column(name = "name")
String name;
}
#Table(name = "account")
public class Account {
#OneToOne(cascade = CascadeType.ALL, optional = false, fetch = FetchType.LAZY)
#JoinColumn(name = "user_id", nullable = false)
#NotNull
User user;
#Column(name = "title")
String title;
}
The problem is when I make that POST request above, it throws an error because user_id is missing, since that's required for the join, but I cannot send the user_id because the User has not yet been created.
Is there a way to create both entities in a single API call?
Since it is a bi-directional relation, and one-to-one is a mandatory in this case, you should persist a user entity and only then persist an account. And one more thing isn't clear here is db schema. What are the pk's of entities? I coukd offer to use user.id as a single identity for both of tables. If so, entities would be as:
User(id, name), Account(user_id, title) and its entities are:
#Table(name = "account")
#Entity
public class Account {
#Id
#Column(name = "user_id", insertable = false, updatable = false)
private Long id;
#OneToOne(mappedBy = "account", fetch = FetchType.LAZY, optional = false)
#MapsId
private User user;
#Column(name = "title")
private String title;
}
#Table(name = "user")
#Entity
public class User {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;;
#OneToOne(cascade = CascadeType.ALL, orphanRemoval = true, fetch = FetchType.LAZY)
#JoinColumn(name = "id", referencedColumnName = "user_id")
private Account account;
#Column(name = "name")
private String name;
}
at the service layer you must save them consistently:
#Transactional
public void save(User userModel) {
Account account = user.getAccount();
user.setAccount(null);
userRepository.save(user);
account.setUser(user);
accountRepository.save(account);
}
it will be done within a single transaction. But you must save the user first, coz the user_id is a PK of the account table. #MapsId shows that user's id is used as an account's identity
Another case is when account's id is stored in the user table:
User(id, name, account_id), Account(id, title) and entities are:
#Table(name = "account")
#Entity
public class Account {
#Id
#Column(name = "id")
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
#OneToOne(cascade = CascadeType.ALL, mappedBy = "account")
private User user;
#Column(name = "title")
private String title;
}
#Table(name = "user")
#Entity
public class User {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
#Column(name = "account_id", insertable = false, updatable = false)
private Long accountId;
#OneToOne(cascade = CascadeType.ALL, orphanRemoval = true, fetch = FetchType.LAZY)
#JoinColumn(name = "account_id", referencedColumnName = "id", unique = true)
private Account account;
#Column(name = "name")
private String name;
}
in this case an Account entity will be implisitly persisted while User entity saving:
#Transactional
public void save(User userModel) {
userRepository.save(user);
}
will cause an insertion into the both of tables. Since cascade and orphane are declared, for deletion would be enough to set null for the account reference:
user.setAccount(null);
userRepository.save(user);

Why Hibernate provides me only interceptor and I catch JdbcSQLIntegrityConstraintViolationException: NULL not allowed?

I would be very grateful to you for help.
I use Spring Boot 2.5.2.
DB: H2 with Liquibase
I need to change ticket History when attachment is removed.
This is my entities:
Ticket:
#Entity
#Data
#AllArgsConstructor
#NoArgsConstructor
public class Ticket {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
#JoinColumn(name = "user_owner_id", nullable = false)
private User owner;
#OneToMany(mappedBy = "ticket", orphanRemoval = true)
private List<Attachment> attachments;
#OneToMany(mappedBy = "ticket", orphanRemoval = true)
private List<History> history;
// other fields and relationships
}
User:
#Entity
#Table(name = "users")
#Data
#AllArgsConstructor
#NoArgsConstructor
public class User {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#OneToMany(mappedBy = "owner", orphanRemoval = true)
private List<Ticket> ownerTickets;
// other fields and relationships
}
Attachment:
#Entity
#Data
#AllArgsConstructor
#NoArgsConstructor
public class Attachment {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private String filename;
#Column(columnDefinition = "bytea")
private byte[] file;
#ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
#JoinColumn(name = "ticket_id", nullable = false)
private Ticket ticket;
#ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
#JoinColumn(name = "user_id", nullable = false)
private User user;
}
History:
#Entity
#Data
#AllArgsConstructor
#NoArgsConstructor
public class History {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#CreationTimestamp
#Column(name = "changed_date", nullable = false, updatable = false)
private LocalDateTime changedDate;
private String action;
private String description;
#ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
#JoinColumn(name = "ticket_id")
private Ticket ticket;
#ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
#JoinColumn(name = "user_id", nullable = false)
private User user;
}
Services:
JpaAttachmentService:
#Service
#AllArgsConstructor
public class JpaAttachmentService implements AttachmentService {
private final AttachmentRepository attachmentRepository;
private final HistoryService historyService;
#Transactional
#Override
public void delete(Long id, Long ticketId, Long userId) {
var attachment = attachmentRepository.getByIdAndTicketIdAndTicketOwnerId(id, ticketId, userId);
var action = "File is removed";
var description = "File is removed: " + attachment.getFilename();
var ticket = attachment.getTicket();
var user = attachment.getUser();
var history = new History(null, LocalDateTime.now(), action, description, ticket, user);
historyService.save(history);
attachmentRepository.deleteByIdAndTicketIdAndTicketOwnerId(id, ticketId, userId);
}
}
When I try to 'historyService.save(history)' I catch:
Caused by: org.h2.jdbc.JdbcSQLIntegrityConstraintViolationException: NULL not allowed for column "USER_ID"; SQL statement:
update history set action=?, description=?, ticket_id=?, user_id=? where id=? [23502-200]
at org.h2.message.DbException.getJdbcSQLException(DbException.java:459)
at org.h2.message.DbException.getJdbcSQLException(DbException.java:429)
at org.h2.message.DbException.get(DbException.java:205)
at org.h2.message.DbException.get(DbException.java:181)
at org.h2.table.Column.validateConvertUpdateSequence(Column.java:374)
at org.h2.table.Table.validateConvertUpdateSequence(Table.java:845)
at org.h2.command.dml.Update.update(Update.java:176)
at org.h2.command.CommandContainer.update(CommandContainer.java:198)
at org.h2.command.Command.executeUpdate(Command.java:251)
at org.h2.jdbc.JdbcPreparedStatement.executeUpdateInternal(JdbcPreparedStatement.java:191)
at org.h2.jdbc.JdbcPreparedStatement.executeUpdate(JdbcPreparedStatement.java:152)
at com.zaxxer.hikari.pool.ProxyPreparedStatement.executeUpdate(ProxyPreparedStatement.java:61)
at com.zaxxer.hikari.pool.HikariProxyPreparedStatement.executeUpdate(HikariProxyPreparedStatement.java)
at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.executeUpdate(ResultSetReturnImpl.java:197)
... 144 more
This is 'var user' debug:
picture
I can't understand why I get this Hibernate Interceptor but not entity. I confused when I see inside interceptor required UserID and when I see 'null' outside of it. Could you help me with this problem, please?
Thanks in advance for any help.
The exception message is quite informative regarding the error you are experiencing. Take a look at the following part:
NULL not allowed for column "USER_ID"; SQL statement: update history
set action=?, description=?, ticket_id=?, user_id=? where id=?
What you attempt to do is to save an instance of a History entity which without passing in a reference to a User object. Since your relation dictates that the user reference cannot be null:
#ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
#JoinColumn(name = "user_id", nullable = false)
To fix this, either make sure that a non-null reference to a User object is passed in when inserting/updating the History reference, or modify your database constraint design to allow for null user references at the History entity.
My problem was related to test, but in the further development I faced it again. So I want to share my solution.
Maybe it will help you.
Pay attention to CascadeType! Cascading operations must be specified above the link to the child relation. In my case, I have to remove this relation or leave Ticket with CascadeType.PERSIST
Fixed class Attachment:
#Entity
#Data
#AllArgsConstructor
#NoArgsConstructor
public class Attachment {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private String filename;
#Column(columnDefinition = "bytea")
private byte[] file;
#ManyToOne(fetch = FetchType.LAZY) // or cascade = CascadeType.PERSIST
#JoinColumn(name = "ticket_id", nullable = false)
private Ticket ticket;
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "user_id", nullable = false)
private User user;
}

How to add movie_id and user_id in "movie_added_by" table

I have already a user model.
Now I have created a movie model, my requirement is that whenever any existing user is going to add any movie, at that time user_id and movie_id will be store in the movie_added_by table.
Here user model needs to map one to many to movie_added_by and similarly, the movie will be mapped to movie_added_by.
For better understanding, you can refer to the DB diagram.
I really don't know how can I do by using hibernate annotation
The user model is like this:
#Getter
#Setter
public class User {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "user_id", unique = true, nullable = false)
private Integer user_id;
private String name;
}
The movie model is like this:
#Getter
#Setter
public class Movie implements Serializable
{
private static final long serialVersionUID = -6790693372846798580L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "movie_id", unique = true, nullable = false)
private Integer movie_id;
private String movie_name;
}
You probably want to create a #ManyToMany relationship between the entities. There are 2 ways of doing it (with intermediary table created explicitly or by Hibernate.
In simple approach your entities would look as following:
public class User {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "user_id", unique = true, nullable = false)
private Integer user_id;
private String name;
#ManyToMany(cascade = CascadeType.Persist)
#JoinTable(name="user_movie",
joinColumns = {#JoinColumn(name="user_id")},
inverseJoinColumns = {#JoinColumn(name="movie_id)})
private Set<Movie> movies = new HashSet<>();
}
public class Movie implements Serializable
{
private static final long serialVersionUID = -6790693372846798580L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "movie_id", unique = true, nullable = false)
private Integer movie_id;
private String movie_name;
#ManyToMany(cascade = CascadeType.Persist, mappedBy = "movies" //field from the user class responsible for mapping)
private Set<User> users = new HashSet<>()
}
So basically here you tell Hibernate to create an intermediary table and keep there correlated id's of those 2 entities. Couple of other notes here:
a) you might want to change the id variable type from Integer to Long in case your entities grow;
b) If you have annotated a column with #Id, you don't have to use unique=true and nullable = false in the column annotation;
c) remember about implementing no-args constructor;
d) remember to exclude relationship fileds from the equals(), hashCode() and the toString() methods;
There is another way, where you explicitly create a model for the table keeping relationships. This might become handy, when it turns out that You need to keep more data in the 'relationship table'. In that case, Your entities would look as following:
public class User {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "user_id", unique = true, nullable = false)
private Integer user_id;
private String name;
#OnetToMany(cascade = CascadeType.PERSIST, mappedBy = "user")
private Set<AddedMovie> addedMovies = new HashSet<>()
}
public class Movie implements Serializable
{
private static final long serialVersionUID = -6790693372846798580L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "movie_id", unique = true, nullable = false)
private Integer movie_id;
private String movie_name;
#OneToMany(cascade = CascadeType.PERSIST, mappedBy = "movie")
private Set<AddedMovie> moviesAddedByUser = new HashSet<>();
}
#Data
#AllArgsConstructor
#NoArgsConstructor
#Builder
#Entity
public class AddedMovie{
#Id
#GeneratedValue
private Long id;
#ManyToOne(cascade = CascadeType.PERSIST)
#JoinColumn(name = "user_id")
private User user;
#ManyToOne(cascade = CascadeType.PERSIST)
#JoinColumn(name = "movie_id")
private Movie movie;
// sine this entity has now its own lifecycle, you can add more fields here
private Integer rating;
private LocalDateTime movieAddedOn;
}

How to have a join table with relationship between 3 entities(USER,Organization and Roles)

I have a scenerio where one staff can belong to multiple organisation and for each organisation he can have different role. How can i map this in jpa?
Staff.java
public class Staff {
#ManyToMany
#JoinTable(name="STAFF_ORGANIZATION",joinColumns=#JoinColumn(name="staff_id"),inverseJoinColumns=#JoinColumn(name="organization_id"))
private Set<Organization> organizations;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;
}
Organization.java
public class Organization {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;
#Column
private String OrganizationName;
#ManyToMany(mappedBy="organizations")
private Set<Staff> staff;
}
StaffRoles.java
public class StaffRoles {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;
#Column
#Enumerated(EnumType.ORDINAL)
private Roles roles;
public enum Roles {
USER(100), ADMIN(200);
private int values;
Roles(int values) {
this.values = values;
}
public int getValues() {
return values;
}
}
Can anyone please help me in mapping the roles to the staff. So many staff can belong to many organisation and for each organisation he can have different role.
Any help will be highly appreciated!
Althought this question is not written clearly I will answer your question based on what I have understood.
Below is an ER-diagram for how your tables might look like.
Now you just need to create the classes needed.
User.java
Organization.java
UserOrganization.java
UserRole.java
Connect the right instance variables now via ManyToMany and OneToOne to achieve your goal.
EDIT:
After the question has been updated with more specific information, I can aid more in this answer. First make a StaffOrganizationRoles class that will sit between StaffOrganization and Roles. Next, make StaffOrganization sit between Staff and Organization, which means that instead of ManyToMany it will be ManyToOne from Staff -> StaffOrganization, and ManyToOne from Organization > StaffOrganization.
public class StaffOrganizationRoles {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "stafforganization_id", unique = false, nullable = false)
private StaffOrganization user;
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "role_id", unique = false, nullable = false)
private Role role;
}
Staff organization class:
public class StaffOrganization {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "staff_id", unique = false, nullable = false)
private Staff staff;
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "organization_id", unique = false, nullable = false)
private Organization organization;
#OneToMany(fetch = FetchType.LAZY, mappedBy = "staffOrganization")
private Set<StaffOrganizationRoles> staffOrganizationRoles = new HashSet<>(0);
}
I've edited the picture above to represent the new ER-diagram.
Hope this will help you now.

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