Hibernate novice here, running into issues trying to properly map the relationships between my Hibernate Entity classes.
I have a Ticket Entity and a User Entity. A user has many tickets, but a ticket only belongs to one unique user. What i've done is mapped the User - Tickets as a #OneToMany relationship and the Tickets - User as a #ManyToOne relationship. However, I am not getting any tickets returned.
The Query Hibernate is running is:
Hibernate: select tickets0_.user_user_id as user1_1_3_, tickets0_.tickets_ticket_id as tickets2_3_, ticketenti1_.ticket_id as ticket1_0_0_, ticketenti1_.assigned_to_user_id as assigned7_0_0_, ticketenti1_.belongs_to_user_id as belongs8_0_0_, ticketenti1_.date_created as date2_0_0_, ticketenti1_.description as descript3_0_0_, ticketenti1_.status_id as status4_0_0_, ticketenti1_.title as title0_0_, ticketenti1_.urgency_id as urgency6_0_0_, userentity2_.user_id as user1_1_1_, userentity2_.email as email1_1_, userentity2_.firstname as firstname1_1_, userentity2_.lastname as lastname1_1_, userentity2_.password as password1_1_, userentity2_.role_id as role6_1_1_, userentity2_.username as username1_1_, userentity2_.verified as verified1_1_, userentity3_.user_id as user1_1_2_, userentity3_.email as email1_2_, userentity3_.firstname as firstname1_2_, userentity3_.lastname as lastname1_2_, userentity3_.password as password1_2_, userentity3_.role_id as role6_1_2_, userentity3_.username as username1_2_, userentity3_.verified as verified1_2_ from user_ticket tickets0_ inner join ticket ticketenti1_ on tickets0_.tickets_ticket_id=ticketenti1_.ticket_id left outer join user userentity2_ on ticketenti1_.assigned_to_user_id=userentity2_.user_id left outer join user userentity3_ on ticketenti1_.belongs_to_user_id=userentity3_.user_id where tickets0_.user_user_id=?
The Entity Classes are:
TicketEntity.java
#Entity
#Table(name="ticket")
public class TicketEntity {
#Id
#Column(name="ticket_id")
#GeneratedValue(strategy=GenerationType.AUTO)
private int id;
#Column(name="title")
private String title;
#Column(name="description")
private String description;
#Column(name="date_created")
#Temporal( TemporalType.TIMESTAMP )
private Date date_created;
#Column(name="status_id")
private int status_id;
//private TicketStatus status;
#Column(name="urgency_id")
private int urgency_id;
#ManyToOne
#JoinColumn(insertable=false, updatable=false)
private UserEntity belongs_to;
#ManyToOne
#JoinColumn(insertable=false, updatable=false)
private UserEntity assigned_to;
UserEntity.java
#Entity
#Table(name="user")
public class UserEntity {
#Id
#Column(name="user_id")
#GeneratedValue(strategy=GenerationType.AUTO)
private int id;
#Column(name="firstname")
private String firstname;
#Column(name="lastname")
private String lastname;
#Column(name="username")
private String username;
#Column(name="email")
private String email;
#Column(name="password")
private String password;
#Transient
private String confirmpassword;
#Column(name="verified")
private boolean verified;
#Column(name="role_id")
private int role_id;
#OneToMany(fetch = FetchType.EAGER)
private List<TicketEntity> tickets;
Any help is appreciated,
Thanks!
In UserEntity.java, you need to add "mappedBy" for List<TicketEntity> tickets, like this:
#OneToMany(fetch = FetchType.EAGER, mappedBy="belongs_to")//why you have two UserEntity in TicketEntity.java?
private List<TicketEntity> tickets;
In TicketEntity.java, add (name = "user_id") to #JoinColumn for UserEntity belongs_to, like this:
#ManyToOne
#JoinColumn(name = "user_id", insertable=false, updatable=false)
private UserEntity belongs_to;
Same for private UserEntity assigned_to. You may need add another list for it in UserEntity.java if you want to query it too.
Related
With the query Select c from Card c join User u on c.userId=u.userId where u.username=':u', I am trying to grab a list of Cards for the User based on the username available in User the table. However, I am running into the antlr.SemanticException: could not resolve property: userId of: com.abc.SheridanSportsWAR.entity.Card exception when I run it. How do I reference the UserId column in my Card entity?
Card.java
#Entity
public class Card {
#Id
#Column(name="CardId")
#GeneratedValue(strategy = GenerationType.AUTO)
private Integer cardId;
#Column(name="CardNumber")
private String cardNumber;
#Column(name="CardType")
private String cardType;
#Column(name="ExpiryMonth")
private String expiryMonth;
#Column(name="ExpiryYear")
private String expiryYear;
#Column(name="CardHolder")
private String cardHolder;
#ManyToOne(cascade = {CascadeType.MERGE, CascadeType.DETACH, CascadeType.PERSIST, CascadeType.REFRESH})
#JoinColumn(name = "UserId")
private User userJ;
#OneToMany(mappedBy = "cardJ")
private List<Purchase> purchases;
User.java
#Entity
public class User {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name="UserId")
private Integer userId;
#Column(name="FirstName")
private String firstName;
#Column(name="LastName")
private String lastName;
#Column(name="Email")
private String email;
#Column(name="Username")
private String username;
#Column(name="Password")
private String password;
#Column(name="RoleName")
private String roleName;
#OneToMany(mappedBy="userJ", cascade= CascadeType.ALL)
private List<Card> cards;
The error message is pretty clear. There is no field userId in your Card entity. Create one like that:
#Column(name = "UserId", insertable=false, updatable=false)
private Integer userId;
AFAIK, the problem seems to be that there's no userId column in the card table.
I've got following two tables:
Customer
id
name
Order
id
product_name
customer_id
with a 1 to 1 relation
and java entities:
#Data
public class Customer{
#Id
private Long id;
private String name;
}
#Data
public class Order{
#Id
private Long id;
#Column("id")
private Customer customer; //i want to somehow map this
private String productName;
}
and a controller
#Controller
public class MyController{
//...
#GetMapping("/")
public String getmap(Model m){
System.out.println(repository.findAll()) //prints "nullrows" due to wrong sql statement
return "mytemplate";
}
}
my current issue is, that spring is executing following sql statement:
SELECT Order.id, Order.product_name, Customer.id, Customer.name
FROM Order LEFT OUTER JOIN Customer ON Customer.id = Order.id
what i actually want is to join on Customer.id = Order.customer_id while leaving the classes as they are i.e. the customer reference needs to stay in order.
i've tried every annotation that i could find so far and have made no progress.
EDIT:
I am not allowed to use jpa/hibernate
One workaround is to do the following:
#Data
public class Customer{
#Id
private Long id;
private String name;
}
#Data
public class Order{
#Id
private Long customerId;
private Long id;
#Column("id")
private Customer customer; //i want to somehow map this
private String productName;
}
causing this to automatically join on Customer.id = Order.customer_id
This does not look like a good fix however.
You can use #OneToOne and #JoinColumn annotations for your One-to-One relationship:
#Data
public class Customer{
#Id
#Column(name = "id")
private Long id;
#Column(name = "name")
private String name;
#OneToOne(cascade = CascadeType.ALL)
#JoinColumn(name = "order_id", referencedColumnName = "id")
private Order order;
}
#Data
public class Order{
#Id
#Column(name = "id")
private Long id;
#Column(name = "product_name")
private String productName;
#OneToOne(cascade = CascadeType.ALL)
#JoinColumn(name = "customer_id", referencedColumnName = "id")
private Customer customer;
}
I am doing an application where I need 2 entities: User and Car.
public class User{
private long id;
private String name;
}
public class Car{
private long id;
private User firstUser;
private User secondUser;
}
So my table cars_info info will contain
RENT(date), FIRST_USER(id), SECOND_USER(id)
How do I connect this using hibernate? I need unidirectional relation. I tried OneToOne, ManyToOne but neither of that works.
Check that you're properly naming the column on your CAR table vs the reference column on the USER table. Example below:
#Entity
#Table(name = "USER")
public class User {
#Id
#Column(name = "USER_ID")
private long id;
#Column(name = "NAME")
private String name;
}
#Entity
#Table(name = "CAR")
public class Car {
#Id
#Column(name = "CAR_ID")
private long id;
#ManyToOne
#JoinColumn(name = "FIRST_USER_ID", referencedColumnName = "USER_ID")
private User firstUser;
#ManyToOne
#JoinColumn(name = "SECOND_USER_ID", referencedColumnName = "USER_ID")
private User secondUser;
}
I can't make my foreign keys auto generate using hibernate and jpa with annotations. Everything seems ok, The entries are saved in database. All the date come from one form which, when submited creates an User object with ModelAttribute and then saves it in Database.
Here are my beans. Anything else i should add ?
#Entity
#Table(name="adress")
public class Adress implements Serializable {
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
#Column(name="adress_id")
private Integer adressId;
#NotBlank(message="The city must be completed")
#Column(name="city")
#Size(min=5,max=30)
private String city;
#NotBlank(message="The street must be completed")
#Column(name="street")
#Size(min=5,max=30)
private String street;
#NotNull(message="The street number must be completed")
#NumberFormat
#Column(name="street_no")
private Integer streetNo;
#OneToOne
#JoinColumn(name="user_id")
private User user;}
and the other one:
#Entity
#Table(name="users")
public class User implements Serializable {
#Id
#Column(name="user_id")
#GeneratedValue(strategy=GenerationType.AUTO)
private Integer userId;
#NotBlank(message="Username can't be blank")
#Size(min=5,max=30)
#Column(name="username")
private String username;
#NotBlank(message="Password field can't be blank")
#Size(min=5,max=30)
#Column(name="password")
private String password;
#NumberFormat
#NotNull(message="Age field must not be blank")
#Column(name="age")
private Integer age;
#Column(name="message")
#Size(min=0,max=100)
private String message;
#Column(name="date")
#DateTimeFormat(pattern="dd/mm/yyyy")
private Date dateCreated;
#OneToOne(mappedBy="user",cascade=CascadeType.ALL,fetch=FetchType.EAGER)
private Adress adress;
+getters and setters for them
public void save(T entity){
sessionFactory.getCurrentSession().save(entity);
}
If I understand you correctly and you're trying to get Hibernate to set the foreign key on your related record this might help. Try getting rid of mappedBy and instead specify the JoinColumn. This works for me on a one to many:
The order:
#Entity
#Table(name = "`order`")
public class Order implements Serializable {
#Id
#GeneratedValue
private Long id;
// Order columns...
#OneToMany(cascade = CascadeType.ALL)
#JoinColumn(name = "order_id")
private Set<Item> items;
}
The item:
#Entity
#Table(name = "item")
public class Item implements Serializable {
#Id
#GeneratedValue
private Long id;
// Item columns...
#ManyToOne(optional = false)
#JoinColumn(name = "order_id", referencedColumnName = "id", nullable = false)
private Order order;
}
in adress class
#OneToOne(mappedBy="adress")
private User user;
and in user class
#OneToOne(cascade=CascadeType.ALL,fetch=FetchType.EAGER,optional=false)
#PrimaryKeyJoinColumn
private Adress adress;
I have the following two classes, one ReqCandAssociation can have many Comments and it is mapped like so. I need to figure out a way that when I delete a ReqCandAssociation it deletes all of its associated comments. Thanks
#Entity
#Table(name = "candidate_jobReq")
public class ReqCandAssociation implements Serializable {
#Id
private Integer candidateId;
#Id
private Integer jobId;
#Column(name = "reqStatus")
private String reqStatus;
#ManyToOne
#PrimaryKeyJoinColumn(name="candidateId", referencedColumnName="id")
private Candidate candidate;
#ManyToOne
#PrimaryKeyJoinColumn(name="jobId", referencedColumnName="id")
private JobReq jobReq;
public ReqCandAssociation(){
}
Second class
#Entity
#Table(name="comment")
public class Comment {
#Id
#GeneratedValue(strategy=GenerationType.IDENTITY)
private Integer id;
#Column(name="commentText")
private String commentText;
#Column(name="commentDate")
private Date commentDate;
#ManyToOne
#PrimaryKeyJoinColumn(name="reqCandAssociationId", referencedColumnName="id")
private ReqCandAssociation reqCandAssociation;
#ManyToOne
#PrimaryKeyJoinColumn(name="userId", referencedColumnName="id")
private User user;
Change this to the following, i'm making it bidirectional mapping.
#Entity
#Table(name = "candidate_jobReq")
public class ReqCandAssociation implements Serializable {
#Id
private Integer candidateId;
#Id
private Integer jobId;
#Column(name = "reqStatus")
private String reqStatus;
#OneToMany(cascade = { CascadeType.ALL }) //this is added here.
#JoinColumn(name ="reqCandAssociationId")
private Set<Comment> comments;
-----
Readup more on the cascade options. All cascade types are all|none|save-update|delete|all-delete-orphan|delete-orphan
The cascade all will delete all the comments associated to this class.