I have some entities (i've left out getters/setters, and some other fields):
#Entity
public class Platform {
#Id
#GeneratedValue
private UUID id;
#OneToMany(mappedBy = "platform", cascade = CascadeType.ALL)
List<PlatformDq> platformDqs = new ArrayList<PlatformDq>();
}
#Entity
public class PlatformDq {
#EmbeddedId
private PlatformDqId platformDqId;
#ManyToOne
#MapsId("platformId")
#JoinColumn(name = "id")
private Platform platform;
}
#Embeddable
public class PlatformDqId {
#Column(name = "platform_id")
private UUID platformId;
#Column(name = "dq")
private String dq;
}
This composite primary key is platform_id and dq columns.
platform_id is also a foreign key.
I want the PlatformDq's platform_id to be generated the same time as the Platform's id.
That is, when I create a new Platform with some PlatformDqs, the composite key platform_id should have the same id as id on Platform, and the dq field is set to some value.
When I try and do it this way, hibernate tells me:
attempted to assign id from null one-to-one property
Just looking at the error it seems that Platform entity part of PlatformDq is not initialized.
Try setting the following as that will explicitly tell jpa of the relationship and further what value to populate for the platform id.
Platform p = new Platform();
//Required Setters
//for each PlatformDq
PlatformDq dq = new Platform();
//Setters
dq.setPlatform(p);
Related
Hi I have couple of Entity classes as below, using lombok for getter and setters
Parent Entity Class have
#Table(name = "PARTY")
#Entity
public class Party {
#Id
#Column(name = "PARTY_ID")
private Long partyId;
#OneToMany(targetEntity = DVLoanParticipants.class,cascade = CascadeType.ALL)
#JoinColumn(name = "PARTY_ID")
#MapKey(name="dvpParticipantName")
#LazyCollection(LazyCollectionOption.FALSE)
private Map<String, DVLoanParticipants> dvLoanParticipantsMap;
}
Child Entity Class have
#Table(name = "DV_LOAN_PARTICIPANTS")
#Entity
public class DVLoanParticipants implements Serializable {
#Id
#Column(name = "PARTY_ID")
private Long partyId;
#Id
#Column(name = "DVP_PARTICIPANT_NAME")
private String dvpParticipantName;
#Column(name = "DVP_PARTICIPANT_TYPE")
private String dvpParticipantType;
}
In service class i am calling save operation as
repository.save(parentEntityObject);
I am able to execute update statements ,but when i try to insert new row for child entity class i am getting an error saying
cannot insert NULL into ("ABC"."DV_LOAN_PARTICIPANTS"."PARTY_ID")
But if i print the parentEntityObject just before the save operation i see the values like
(partyId=12345678, dvpParticipantName=XYZ, dvpParticipantType=VKP)
I see the query formed as
insert
into
DV_LOAN_PARTICIPANTS
(DVP_PARTICIPANT_TYPE, PARTY_ID, DVP_PARTICIPANT_NAME)
values
(?, ?, ?)
Just before te save i am seeing valules in the Object
Builder=DVLoanParticipants(partyId=123456, dvpParticipantName=Builder,
dvpParticipantType=Individual)
Update
This is the setting part for values
DVLoanParticipants dvLoanParticipants = new
DVLoanParticipants();
dvLoanParticipants.setPartyId(Long.valueOf(partyId));
dvLoanParticipants.setDvpParticipantName("Builder");
dvLoanParticipants.setDvpParticipantType("Individual");
Party party = new Party();
Map<String, DVLoanParticipants> dvLoanParticipantsMap = new
java.util.HashMap<>();
dvLoanParticipantsMap.put("Builder", dvLoanParticipants);
party.setPartyId(Long.valueOf(partyId));
party.setDvLoanParticipantsMap(dvLoanParticipantsMap);
repository.save(party);
What is the mistake i am doing ?
The root cause of your problem in this part:
#OneToMany(targetEntity = DVLoanParticipants.class,cascade = CascadeType.ALL)
#JoinColumn(name = "LOAN_ID")
#MapKey(name="dvpParticipantName")
private Map<String, DVLoanParticipants> dvLoanParticipantsMap;
actually for your case the column name in the #JoinColumn means:
If the join is for a unidirectional OneToMany mapping using a foreign key mapping strategy, the foreign key is in the table of the target entity.
So, assuming for the clarity that you want to map the following schema:
create table PARTY
(
PARTY_ID int,
-- ...
primary key (PARTY_ID)
);
create table DV_LOAN_PARTICIPANTS
(
PARTY_ID int,
DVP_PARTICIPANT_NAME varchar(50),
DVP_PARTICIPANT_TYPE varchar(10),
-- ...
primary key (PARTY_ID, DVP_PARTICIPANT_NAME),
foreign key (PARTY_ID) references PARTY(PARTY_ID)
);
You can use the following mapping:
#Entity
#Table(name = "PARTY")
public class Party
{
#Id
#Column(name = "PARTY_ID")
private Long partyId;
// I use fetch = FetchType.EAGER instead of deprecated #LazyCollection(LazyCollectionOption.FALSE)
// targetEntity = DVLoanParticipants.class is redundant here
#OneToMany(cascade = CascadeType.ALL, fetch = FetchType.EAGER)
#JoinColumn(name = "PARTY_ID") // this is DV_LOAN_PARTICIPANTS.PARTY_ID column
#MapKey(name = "dvpParticipantName")
private Map<String, DVLoanParticipants> dvLoanParticipantsMap;
public Party()
{
dvLoanParticipantsMap = new HashMap<>();
}
// getters / setters
public void addParticipant(DVLoanParticipants p)
{
this.dvLoanParticipantsMap.put(p.getDvpParticipantName(), p);
p.setPartyId(getPartyId());
}
}
#Entity
#Table(name = "DV_LOAN_PARTICIPANTS")
public class DVLoanParticipants implements Serializable
{
#Id
#Column(name = "PARTY_ID")
private Long partyId;
#Id
#Column(name = "DVP_PARTICIPANT_NAME")
private String dvpParticipantName;
#Column(name = "DVP_PARTICIPANT_TYPE")
private String dvpParticipantType;
// getters / setters
}
and example how to save:
Party party = new Party();
party.setPartyId(2L);
// ...
DVLoanParticipants part1 = new DVLoanParticipants();
part1.setDvpParticipantName("Name 3");
part1.setDvpParticipantType("T1");
DVLoanParticipants part2 = new DVLoanParticipants();
part2.setDvpParticipantName("Name 4");
part2.setDvpParticipantType("T1");
party.addParticipant(part1);
party.addParticipant(part2);
repository.save(party);
and several notes:
The LazyCollectionOption.TRUE and LazyCollectionOption.FALSE values are deprecated since you should be using the JPA FetchType attribute of the #OneToMany association.
You use hibernate specific approach for mapping сomposite identifiers. As it's mentioned in the hibernate documentation:
The restriction that a composite identifier has to be represented by a primary key class (e.g. #EmbeddedId or #IdClass) is only JPA-specific.
Hibernate does allow composite identifiers to be defined without a primary key class via multiple #Id attributes.
But if you want to achieve more portability you should prefer one of the jpa allowed approaches.
Unable to update entity for optional one to one relationship using spring data jpa(2.1.2.RELEASE) and spring boot(2.1.2.RELEASE)
Getting the error attempted to assign null one-to-one property
#Entity
#Table(name = "table_a")
public class EntityA {
#Id
String id;
String aa;
int bbb;
#Nullable
#OneToOne(mappedBy = "inv", optional = true,cascade = CascadeType.ALL)
EntityB bEntity;
}
#Entity
public class EntityB{
#Id
String id;
String aaa;
String nnnn;
#OneToOne
#MapsId
#JoinColumn(name = "id")
EntityA aEntity;
}
DAO Code as below
Optional eA = entARepo.findById("1234");
EntityA entA= null;
if (eA.isPresent()) {
entA= eA.get();
}
EntityB eB = entA.getBEntity();
if (Objects.isNull(eB)) {
eB= new EntityB();
eB.setAAA("12121");
eB.setAEntity(entA);
entA.setBEntity(entB);
}
repository.save(entA);
}``
I resolved this by using a join table instead of a shared primary key approach. would still to know how to make the shared primary key approach work for optional one to one relationship
I have SpringBoot 2.1.3 and Java 8 application. Building DB with JPA I have 3 table in one to one relationship. Suppose the tables is the follows:
#Entity
#Data //lombok
#Table(name = "users")
public class User {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "id")
private Long id;
#OneToOne(mappedBy = "user", cascade = CascadeType.ALL)
private Address address;
}
And then:
#Entity
#Data
#Table(name = "address")
public class Address {
#Id
#Column(name = "id")
private Long id;
#OneToOne
#MapsId
private User user;
}
That's works.. and it is the best way to do (this exactly example is taken from documentation).
If I start the application the DB is created and if I tried to add entities all works well. The model created follows:
Now I want to add a Country object to my address Entities (for example) and I modified the Entities as follows:
#Entity
#Data
#Table(name = "address")
public class Address {
#Id
#Column(name = "id")
private Long id;
#OneToOne
#MapsId
private User user;
#OneToOne
#MapsId
private Country country;
}
And Country Entities:
#Entity
#Data
#Table(name = "country")
public class Country {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "id")
private Long id;
#OneToOne(mappedBy = "country", cascade = CascadeType.ALL)
private Address address;
}
The application still starts, the DB is created and the model follows:
But if I try to save a User as follows:
User user = new User();
Address address = new Address();
Country country = new Country();
user.setAddress(address);
address.setUser(user);
address.setCountry(country);
country.setAddress(address);
userRepository.save(user);
I obtain the error:
java.sql.SQLException: Field 'country_id' doesn't have a default value
Anyway I solve the issue removing #MapsId and added #JoinColumn but I would like to understand what's wrong.
P.S.: I'm using MySQL 5.7 with InnoDB dialect (setting on application.properties)
Thanks all
It works only with one #MapsId annotation. Using two is causing that country id is not inserted:
insert into Country (id) values (?)
insert into Users (id) values (?)
insert into Address (user_id) values (?)
I have a postgres database and I am trying to make a simple REST service with Spring Boot. I have a problem with jpa ManytoMany relationship.
Person Entity:
#Entity
#Table(name = "person", schema = "persons")
public class Person implements Serializable {
#Id
#GeneratedValue(strategy= GenerationType.IDENTITY)
private Integer id;
#Column(nullable = false)
private String name;
#Column(nullable = false)
private String email;
#Column
private Integer age;
#ManyToOne
#JoinColumn(name = "country_id", referencedColumnName = "id")
private Country countryOfBirth;
#ManyToMany
#JoinTable(
name="persons_countries_residence",
joinColumns=#JoinColumn(name="person_id", referencedColumnName="id"),
inverseJoinColumns=#JoinColumn(name="country_id", referencedColumnName="id"))
private List<Country> countriesOfResidence;
// getters and setters and to String method overriden
}
Country Entity:
#Entity
#Table(name = "country", schema = "persons")
public class Country implements Serializable {
#Id
#GeneratedValue(strategy= GenerationType.IDENTITY)
private Integer id;
#Column(name = "country_name")
private String name;
#Column(name = "country_code")
private String code;
// getters and setters and to String method overriden
}
The postgres schema is the following:
Person Table:
CREATE TABLE persons.person
(
id serial NOT NULL,
name character varying(50) NOT NULL,
email character varying(40) NOT NULL,
age integer,
country_id serial NOT NULL,
CONSTRAINT id PRIMARY KEY (id),
CONSTRAINT country_id FOREIGN KEY (id)
REFERENCES persons.country (id) MATCH SIMPLE
ON UPDATE NO ACTION ON DELETE NO ACTION
)
Country table:
CREATE TABLE persons.country
(
id serial NOT NULL,
country_name character varying(45) NOT NULL,
country_code character varying(10) NOT NULL,
CONSTRAINT country_id PRIMARY KEY (id)
)
Join table:
CREATE TABLE persons.persons_countries_residence
(
person_id integer NOT NULL,
country_id integer NOT NULL,
CONSTRAINT person_country_id PRIMARY KEY (person_id, country_id),
CONSTRAINT persons_countries_residence_country_id_fkey FOREIGN KEY (country_id)
REFERENCES persons.country (id) MATCH SIMPLE
ON UPDATE CASCADE ON DELETE NO ACTION,
CONSTRAINT persons_countries_residence_person_id_fkey FOREIGN KEY (person_id)
REFERENCES persons.person (id) MATCH SIMPLE
ON UPDATE CASCADE ON DELETE CASCADE
)
When i make an HTTP method call, I don't get the Countries of residence.
Service code:
#RequestMapping(method = RequestMethod.GET, produces = {MediaType.APPLICATION_JSON_VALUE, MediaType.APPLICATION_XML_VALUE})
public List<Person> getAllPersons() {
retutn jpaPersonRepository.findAll();
}
Any help appreciated.
Maybe, you need to specify a schema name in the join table name:
#JoinTable(
name="persons_countries_residence", schema="persons",
joinColumns=#JoinColumn(name="person_id", referencedColumnName="id"),
inverseJoinColumns=#JoinColumn(name="country_id", referencedColumnName="id"))
Update your Country class code like :
#Entity
#Table(name = "country", schema = "persons")
public class Country implements Serializable {
#Id
#GeneratedValue(strategy= GenerationType.IDENTITY)
private Integer id;
#Column(name = "country_name")
private String name;
#Column(name = "country_code")
private String code;
#ManyToMany(mappedBy = "countriesOfResidence")
private List<Person> persons;
// getters and setters and to String method overriden
}
Although a ManyToMany relationship is always bi-directional on the
database, the object model can choose if it will be mapped in both
directions, and in which direction it will be mapped in. If you choose
to map the relationship in both directions, then one direction must be
defined as the owner and the other must use the mappedBy attribute to
define its mapping. This also avoids having to duplicate the JoinTable
information in both places.
Do you mean that the country list is null? #ManyToMany associations are lazily loaded by default, you need to enable eager-fetching for it to work straight away.
#ManyToMany(fetch = FetchType.EAGER)
The solution is this:
#ManyToMany
#JoinTable(
name="persons_countries_residence", schema = "persons",
joinColumns=#JoinColumn(name="person_id", referencedColumnName="id"),
inverseJoinColumns=#JoinColumn(name="country_id", referencedColumnName="id"))
private List<Country> countriesOfResidence;
The schema had to be specified at the #JoinTable annotation as well.
I have two tables. I want to make between them relationship, but the thing is that the child table connects to an attribute in a parent node, which is not a PK. How can I assign a non-PK field as a FK for a table?
Here are the tables. User Information:
#Entity
#Table(name="user")
public class userinformation implements Serializable {
#Id
#GeneratedValue(strategy=GenerationType.IDENTITY)
#Column(name="USER_ID")
private int uID;
#Column(name="LIB_ID")
private String libID;
//Other attributes
}
Lib Information
#Entity
#Table(name="libinfo")
public class Auth {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name="AUTH_ID")
private int authID;
#Column(name="LIB_ID")
private String lib_ID;
//Other attributes
}
They both should be linked through libID (surely unique). Any idea how to implement it correctly?
Given:
class User {
#Column(name = "lib_id")
private String libID;
}
you must map the Auth entity as:
class Auth {
#JoinColumn(name = "lib_id", referencedColumnName = "lib_id")
#ManyToOne
private User user;
}
Basically, referencedColumnName is used to inform the JPA provider that it should use a column other than the primary key column of the referenced entity (which is used by default with #ManyToOne mappings).