I have a class with 2 fields marked with #Id
#Entity
#Table(name="baspas")
class BasPas
#Id
#ManyToOne
#JoinColumn(name="bas_id", referenceColumnName="id")
private Bas basboard;
#Id
#ManyToOne
#JoinColumn(name = "pas_id", referenceColumnName = "id")
private pas pasboard;
//
I refactored them to an Embedded class and pulled the above two #Id fields in the BasPasPK class. This will enable me to create an interface which will extend the JPARepository interface.
#Embeddable
class BasPasPK {
#ManyToOne
#JoinColumn(name="bas_id", referenceColumnName="id")
private Bas basboard;
#ManyToOne
#JoinColumn(name = "pas_id", referenceColumnName = "id")
private pas pasboard;
//
}
As both these fields are annotated #ManyToOne there is another end of the relationship, where in these fields are listed with "mappedBy".
for eg.
#Entity
class Another{
.
.
#OneToMany(mappedBy = "basboard" cascade = CascadeType.ALL)
private set<BasPas> basPas;
.
.
.
}
But after refactoring how to access the other end of the class.
What I mean is when I am doing mvn spring-boot:run I am getting the following exception
org.hibernate.AnnotationException: mappedBy reference an unknown target entity property
then what I did was to change the class name in
#Entity
class Another{
.
.
#OneToMany(mappedBy = "basboard" cascade = CascadeType.ALL)
private Set<BasPas> basPas;
.
.
.
}
to this
class Another{
.
.
#OneToMany(mappedBy = "bas" cascade = CascadeType.ALL)
private set<BasPasPk> basPas; //changed the classname in angle brackets to BasPasPk
.
.
.
}
But after this I started getting this following exception.
org.hibernate.AnnotationException: Use of #OneToMany or #ManyToMany targeting an unmapped class.
How to fix this, I mean how to access these properties in the other class after pulling those two property in the embedded class.
try it this way: (Assuming the name of the BasPasPK property in your entity is id)
#Entity
class Bas{
.
.
#OneToMany(mappedBy = "id.basboard" cascade = CascadeType.ALL)
private Set<BasPas> basPas;
.
.
.
}
Have you tried annotating the class BasPas with #Entity ?
Related
I have 2 entities and 1 embeddable object :
#Entity
class CourseDetails extends Course {
#Id
Integer id;
#ElementCollection
#CollectionTable(name = "course_section", joinColumns = #JoinColumn(name = "courseId"), foreignKey = #ForeignKey(name = "course_section_fk"))
private List<CourseSection> courseSection;
}
#Embeddable
public class CourseSection extends BaseBo {
#OneToMany
#JoinColumn(name="contentId")
private Set<CourseContent> courseContent = new HashSet<>();
}
#Entity
public class CourseContent {
private static final long serialVersionUID = 1856738483334146418L;
#Id
private Integer contentId;
private String contentSummary;
}
I want to store coursesection as an embedded object of course and course_section should contain reference of course_content. I tried the above structure but it gives error :
#ElementCollection cannot be used inside an #Embeddable that is also contained within an #ElementCollection
How to achieve this in spring boot-jpa ?
I have a problem with JPA inheritance. The database model is also specially built. It contains several tables with the same attributes (the tables were intentionally cut by country) and all these tables connect to another table (OneToOne).
Here is an example of the data model:
usa_user, germany_user, austria_user. All these tables have the same attributes (id, name, address). Now the address was also built up according to the countries e.g. usa_address, germany_address, austria_address.
Now I don't know or have the problem that I have been mapping them correctly for a long time. I have the following:
// All Lombok Getter, Setter Args,...
#MappedSuperclass
public abstract Address {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#JsonIgnore
private Long id;
#OneToOne(cascade = CascadeType.ALL)
#JoinColumn(name = "user_id", referencedColumnName = "id")
#JsonIgnore
private User user;
private String name;
private String addr_num;
...
}
// All Lombok Getter, Setter Args,...
#MappedSuperclass
public abstract User {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#JsonIgnore
private Long id;
#OneToOne(mappedBy = "user", cascade = CascadeType.ALL, fetch = FetchType.LAZY, optional = false)
#JsonIgnore
private Address address;
private String name;
}
#Entity
#Table(name = "usa_user")
public class UsaUser extends User {}
#Entity
#Table(name = "austria_user")
public class AustriaUser extends User {}
#Entity
#Table(name = "germany_user")
public class GermanyUser extends User {}
#Entity
#Table(name = "usa_address")
public class UsaAddress extends Address {}
#Entity
#Table(name = "austria_address")
public class AustriaAddress extends Address {}
#Entity
#Table(name = "germany_address")
public class GermanyAddress extends Address {}
But unfortunately this does not work. Every time I start it JPA notices that it can't map the Entities Address - User (which is understandable because they are not entities but abstract classes). What would be the best way to solve this? I want to avoid that I have to list the attributes in all these entities because it would be redundant.
The goal is to find out how I can use a #MappedSuperclass in a #MappedSuperclass.
MappedSuperclass is not queryable and thus also not joinable. You need to map this as an abstract entity with the table per class inheritance strategy. Just switch to #Entity on the Address and User and add #Inheritance(TABLE_PER_CLASS).
I'm writing 3 tables in the following relation:
Club class:
#Setter
#Getter
#Entity
#Table(name = "Club")
public class Club {
#Id
#GeneratedValue
private Long id;
private String name;
private String type;
private String mainPage;
private String logo;
#OneToMany(mappedBy="clubProductKey.club", cascade = CascadeType.ALL)
#JsonIgnoreProperties(value = "clubProductKey.club", allowSetters=true)
private Set<ClubProduct> clubProducts;
...
Product class:
#Setter
#Getter
#Entity
#Table(name = "Product")
public class Product {
#Id
#GeneratedValue
private Long id;
#OneToMany(mappedBy="clubProductKey.product", cascade = CascadeType.ALL)
#JsonIgnoreProperties(value = "clubProductKey.product", allowSetters=true)
private Set<ClubProduct> clubProducts;
...
ClubProduct class:
#Setter
#Getter
#Entity
#Table(name = "ClubProduct")
public class ClubProduct {
#EmbeddedId
private ClubProductKey clubProductKey;
...
ClubProductKey class:
#Setter
#Getter
#Embeddable
public class ClubProductKey implements Serializable {
#ManyToOne(cascade = {CascadeType.MERGE,CascadeType.REFRESH })
#JoinColumn(name = "club_id", referencedColumnName = "id")
#JsonIgnoreProperties(value = "clubProducts", allowSetters=true)
private Club club;
#ManyToOne(cascade = {CascadeType.MERGE,CascadeType.REFRESH })
#JoinColumn(name = "product_id", referencedColumnName = "id")
#JsonIgnoreProperties(value = "clubProducts", allowSetters=true)
private Product product;
...
ClubProductRepository class:
public interface ClubProductRepository extends JpaRepository<ClubProduct, ClubProductKey> {
public List<ClubProduct> findByClubProductKeyClub(Club club);
public List<ClubProduct> findByClubProductKeyProduct(Product product);
}
I try to save clubProduct like this:
#Service
public class ClubProductServiceImp implements ClubProductService {
#Autowired
private ClubProductRepository clubProductRepository;
...
ClubProduct savedClubProduct = clubProductRepository.save(clubProduct);
return savedClubProduct;
}
However I find that the clubProduct is not saved in the clubProducts list in the club or product entity, the list is null. Must I add lines like club.getClubProducts.add(clubProduct) or is there any other way to make it added automatically?
Thank you.
The #OnetoMany mapping in your Club class uses the attribute mappedby which means that it represents the owning side of the relation responsible for handling the mapping. However, we still need to have both sides in sync as otherwise, we break the Domain Model relationship consistency, and the entity state transitions are not guaranteed to work unless both sides are properly synchronized.
The answer is yes, you have to manage the java relations yourself so that the clubProducts gets persisted. You are using an instance of the repository class club to persist the data so , you should add a setter method like :
public void addClubProduct(ClubProduct clubProduct) {
if (clubProduct!= null) {
if (clubProduct== null) {
clubProduct= new ArrayList<ClubProduct>();
}
clubProducts.add(clubProduct);
clubProduct.setClubProduct(this);
}
}
also a method to remove it from the list and use these method in your code to set the values to the list properly before initiating save . Read related article
I'm very new to this topic so i followed a tutorial. after following steps i got some build time errors.
I have imported javax persistence like this.
import javax.persistence.*;
Then the student model class
#Entity
#Table(name="STUDENT")
public class Student {
#Id
#GeneratedValue
private Integer studentId;
#ManyToOne(cascade = CascadeType.ALL)
#JoinTable(name="Enrollment", joinColumns = {#JoinColumns(name="student_id")},
inverseJoinColumns = {#JoinColumns(name="course_id")})
private List<Course> courses = new ArrayList<>();
}
The Course model class.
#Entity
#Table(name="COURSE")
public class Course {
#GeneratedValue
private Integer id;
#ManyToMany(mappedBy ="courses")
private List<Student> students = new ArrayList<>();
These are set of errors that i have got
incompatible types: javax.persistence.JoinColumns cannot be converted to javax.persistence.JoinColumn
cannot find symbol
symbol: method name()
location: #interface javax.persistence.JoinColumns
annotation #javax.persistence.JoinColumns is missing a default value for the element 'value'
Can anyone help me to get rid of this issues?
Thanks.
A #JoinTable annotation really has a joinColumns parameter, but the syntax you had used is not correct. If tables are joined by only column and inverse column you shouldn't use a #JoinColumns annotation. You have to change it in the following way:
#Entity
#Table(name="STUDENT")
public class Student {
#Id
#GeneratedValue
private Integer studentId;
#ManyToOne(cascade = CascadeType.ALL)
#JoinTable(
name="Enrollment",
joinColumns = #JoinColumn(name="student_id", referencedColumnName = "id"),
inverseJoinColumns = #JoinColumn(name="course_id", referencedColumnName = "id"))
private List<Course> courses = new ArrayList<>();
}
and only if joining goes by more then one column you have to do something like this:
#Entity
#Table(name="STUDENT")
public class Student {
#Id
#GeneratedValue
private Integer studentId;
#ManyToOne(cascade = CascadeType.ALL)
#JoinTable(
name="Enrollment",
joinColumns = #JoinColumns{
#JoinColumn(name="student_id", referencedColumnName = "id"),
#JoinColumn(name="another_id", referencedColumnName = "another_id")
},
inverseJoinColumns = #JoinColumn(name="course_id", referencedColumnName = "id"))
private List<Course> courses = new ArrayList<>();
}
Hope it will help
When I try to get the users using repository interface I received following exception "org.springframework.dao.InvalidDataAccessApiUsageException: No aliases found in result tuple! Make sure your query defines aliases!; nested exception is java.lang.IllegalStateException: No aliases found in result tuple! Make sure your query defines aliases!"
Repository:
#Repository
public interface UserRelationshipRepository
extends JpaRepository<UserRelationship, Long>, QueryDslPredicateExecutor<UserRelationship> {
#Query(value = "SELECT ur.id.toUser FROM UserRelationship ur WHERE ur.fromUser = :fromUser AND ur.relationshipTypeId = 1")
Set<User> findUserFriends(#Param("fromUser") User fromUser);
}
Entities:
#Entity
#NamedEntityGraph(name = "graph.User", attributeNodes = {})
#Table(name = "users")
public class User extends BaseEntity implements UserDetails {
private static final long serialVersionUID = 8884184875433252086L;
#Id
#SequenceGenerator(name = "users_id_seq", sequenceName = "users_id_seq", allocationSize = 1)
#GeneratedValue(strategy = GenerationType.AUTO, generator = "users_id_seq")
private Long id;
#Column(name = "first_name")
private String firstName;
#OneToMany(fetch = FetchType.LAZY, mappedBy = "fromUser", cascade = CascadeType.ALL)
private Set<UserRelationship> relationships = new HashSet<UserRelationship>();
// getters setters
}
#Entity
#NamedEntityGraph(name = "graph.UserRelationship", attributeNodes = {})
#Table(name = "users_relationships")
public class UserRelationship extends BaseEntity implements Serializable {
private static final long serialVersionUID = -6367981399229734837L;
#EmbeddedId
private final UserRelationshipId id = new UserRelationshipId();
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "from_user_id", nullable = false)
#MapsId("fromUserId") // maps fromUserId attribute of the embedded id
private User fromUser;
#Column(name = "relationship_type_id")
private Long relationshipTypeId;
}
I am using '1.11.0.BUILD-SNAPSHOT' version of spring data jpa.
This is already known issue, and it is marked as resolved, but I am still get it.
Please, help me to solve this.
Update:
If I change repository method's return type to Set<Object> then all works fine.
You're running into DATAJPA-885, which is already fixed and will be part of the Spring Data Hopper SR2 release.