I have three tables EmployeeDepartment, EmployeeGroup and EmpplyeeDetails Table. EmployeeDepartment table has primary key departmentId and a column groupId, EmployeeGroupTable has primary key groupid which should be generated from databse sequence GroupIdGenerator.
EmployeeDetails have two primary keys as groupid and employeeid. Groupid should be same as of the previous table
These values in all table should insert in one transaction.
Can you help me with correct JAP Entity mapping?
I already tried with different combination of Generated value and Sequence generator but not able to save the data into table.
#Entity
#Table(name="EMPLOYEE_DEPARTMENT")
public class EmployeeDepartment {
#Column(name = "DEPARTMENT_ID")
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator =
"departmentid-gen")
#Id
#NotNull
#SequenceGenerator(name = "departmentid-gen", sequenceName =
"DEAPARTMENT_ID_GENERATOR" )
private long departmentId;
#OneToOne(mappedBy = "employeeGroup")
private EmployeeGroup employeeGroup;
}
#Coulmn(name="GROUP_ID")
private long groupId;
#Entity
#Table(name="EMPLOYEE_GROUP")
public class EmployeeGroup {
#Column(name = "GROUP_ID")
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator =
"groupid-gen")
#Id
#NotNull
#SequenceGenerator(name = "groupid-gen", sequenceName =
"GROUIP_ID_GENERATOR" )
private long groupId;
#OneToMany(mappedBy = "employeeDetail")
private List<EmployeeDetail> employeeDetails;
#OneToOne
#JoinColumn(name = "DEPARTMENT_ID", insertable=false ,
updatable=false)
private EmployeeDepartment employeeDepatment;
}
#Entity
#Table(name = "EMPLOYEE_DETAIL")
#IdClass(EmployeeID.class)
public class EmployeeDetail {
#ManyToOne
#JoinColumn(name = "GROUP_ID", insertable=false , updatable=false)
private EmployeeGroup employeeGroup;
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator =
"groupid-gen")
#SequenceGenerator(name = "groupid-gen", sequenceName =
"GROUIP_ID_GENERATOR" )
#Column(name = "GROUP_ID")
#Nonnull
private Long groupId;
#Id
#Nonnull
#Column(name = "EMPLOYEE_ID")
private Long employeeId;
}
public class EmployeeId{
private Long groupId;
private Long employeeId;
public EmployeeId(final Long groupId, final Long employeeId) {
this.groupId = groupId;
this.employeeId = employeeId;
}
public EmployeeId() {
}
}
Expected result in these 3 tables should have proper values like.
Table EmployeeDepartment
DepartmentID GroupId
1 1
Table EmployeeGroup
GroupID
1
Table EmployeeDetail
GroupId EmployeeId
1 1
1 2
1 3
Actual results are below
Table EmployeeDepartment
DepartmentID GroupId
1 0
Table EmployeeGroup
GroupID
1
Table EmployeeDetail
GroupId EmployeeId
2 1
3 2
4 3
The important annotation is #MapsId("groupId")
Your mapping should be something like this:
#Entity
#Table(name="EMPLOYEE_DEPARTMENT")
public class EmployeeDepartment {
#Column(name = "DEPARTMENT_ID")
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator =
"departmentid-gen")
#Id
#NotNull
#SequenceGenerator(name = "departmentid-gen", sequenceName =
"DEAPARTMENT_ID_GENERATOR" )
private long departmentId;
#OneToOne(mappedBy = "employeeGroup")
private EmployeeGroup employeeGroup;
#Column(name="GROUP_ID")
private long groupId;
#Entity
#Table(name="EMPLOYEE_GROUP")
public class EmployeeGroup {
#Column(name = "GROUP_ID")
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator =
"groupid-gen")
#Id
#NotNull
#SequenceGenerator(name = "groupid-gen", sequenceName =
"GROUIP_ID_GENERATOR" )
private long groupId;
#OneToMany(mappedBy = "employeeDetail")
private List<EmployeeDetail> employeeDetails;
#OneToOne
#JoinColumn(name = "DEPARTMENT_ID", insertable=false, updatable=false)
private EmployeeDepartment employeeDepatment;
#Entity
#Table(name = "EMPLOYEE_DETAIL")
#IdClass(EmployeeID.class)
public class EmployeeDetail {
#MapsId("groupId")
#ManyToOne
#JoinColumn(name = "GROUP_ID", insertable=false , updatable=false)
private EmployeeGroup employeeGroup;
#Id
#Nonnull
#Column(name = "EMPLOYEE_ID")
private Long employeeId;
#Entity
#Table(name="EMPLOYEE_DEPARTMENT")
public class EmployeeDepartment {
#Column(name = "DEPARTMENT_ID")
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator =
"departmentid-gen")
#Id
#NotNull
#SequenceGenerator(name = "departmentid-gen", sequenceName =
"DEAPARTMENT_ID_GENERATOR" )
private Long departmentId;
#OneToOne(mappedBy = "employeeGroup")
private EmployeeGroup employeeGroup;
}
#Column(name="GROUP_ID")
private EmployeeGroup group;
#Entity
#Table(name="EMPLOYEE_GROUP")
public class EmployeeGroup {
#Column(name = "GROUP_ID")
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator =
"groupid-gen")
#Id
#NotNull
#SequenceGenerator(name = "groupid-gen", sequenceName =
"GROUIP_ID_GENERATOR" )
private Long groupId;
#OneToMany(mappedBy = "employeeDetail")
private List<EmployeeDetail> employeeDetails;
#OneToOne
#JoinColumn(name = "DEPARTMENT_ID", insertable=false ,
updatable=false)
private EmployeeDepartment employeeDepatment;
}
#Entity
#Table(name = "EMPLOYEE_DETAIL")
#IdClass(EmployeeID.class)
public class EmployeeDetail {
#Id
#ManyToOne
#JoinColumn(name = "GROUP_ID", insertable=false , updatable=false)
private EmployeeGroup employeeGroup;
#Id
#Nonnull
#Column(name = "EMPLOYEE_ID")
private Long employeeId;
You also need to change the EmployeeId accordingly:
public class EmployeeId{
private EmployeeGroup employeeGroup;
private Long employeeId;
public EmployeeId(final EmployeeGroup employeeGroup, final Long employeeId) {
this.employeeGroup= employeeGroup;
this.employeeId = employeeId;
}
However I haven't use composite keys this way before. If it doesn't work, then change EmployeeId to an embeddedId:
#Embeddable
public class EmployeeId implements Serializable{
#ManyToOne(fetch = FetchType.LAZY, optional = false)
private EmployeeGroup employeeGroup;
#Nonnull
#Column(name = "EMPLOYEE_ID")
private Long employeeId;
public EmployeeId(final EmployeeGroup employeeGroup, final Long employeeId) {
this.employeeGroup= employeeGroup;
this.employeeId = employeeId;
}
#Entity
#Table(name = "EMPLOYEE_DETAIL")
public class EmployeeDetail {
#EmbeddedId
private EmployeeId id;
#ManyToOne
#JoinColumn(name = "GROUP_ID", insertable=false , updatable=false)
private EmployeeGroup employeeGroup;
}
If it still doesn't work, then please attach the code snippet where you create the entities.
Related
I am learning JPA.
I need to create 3 tables, product (pk => id), cart (pk => id), cart_details (pk also fk => product_id, cart_id).
The relation is : One cart can contain multiple cart_details, one cart_details can contain multiple product and one product can be put on multiple cart_details. I need only 3 tables, but JPA creates 4 tables for me: product, cart, cart_details, cart_details_product
#Entity
#Table(name = "product")
public class Product implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private long id;
#NotBlank
#Size(max = 50)
private String name;
#Size(max = 300)
private String description;
#NotNull
private Double price;
private int qty;
#Column(name = "created_date")
private Date createdDate;
#Column(name = "updated_date")
private Date updatedDate;
}
#Entity
#Table(name = "cart")
public class Cart implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#Column(name = "total_price")
private double totalPrice;
#Column(name = "created_date")
private Date createdDate;
#Column(name = "updated_date")
private Date updatedDate;
}
#Entity
#Table(name = "cart_details")
public class CartDetails implements Serializable {
private static final long serialVersionUID = 1L;
#EmbeddedId
private CartDetailsId id;
#MapsId("cartId")
#ManyToOne
#JoinColumn(name = "cart_id", referencedColumnName = "id", insertable = false, updatable = false)
private Cart cart;
#ManyToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
#JoinColumn(name = "product_id", referencedColumnName = "id")
private Set<Product> product;
private int quantity;
private double price;
}
#Embeddable
public class CartDetailsId implements Serializable {
private static final long serialVersionUID = 1L;
#Column(name = "cart_id")
private Long cartId;
#Column(name = "product_id")
private Long productId;
}
How to avoid creation of this table (cart_details_product)? I think i don't need this table.
I defined my model classes like below.
#Entity
#Table(name = "my_employee")
public class Employee {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private int id;
private String name;
#OneToMany(cascade = CascadeType.ALL)
#JoinTable(name = "emp_address_mapping", joinColumns = #JoinColumn(name = "emp_id"), inverseJoinColumns = #JoinColumn(name = "address_id"))
private List<Address> addresses = new ArrayList<Address>();
.......
.......
}
#Entity
#Table(name = "my_address")
public class Address {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private int id;
private String country;
.....
.....
}
public class EmployeeDetails {
private int empId;
private String name;
private String country;
......
......
}
How can I write a query using #Query annotation to populate all the EmployeeDetails.
public interface EmployeeRepository extends CrudRepository<Employee, Integer> {
#Query("SELECT new com.sample.app.model.EmployeeDetails......")
List<EmployeeDetails> getEmployeeDetails();
}
Create the constructor in EmployeeDetails
public EmployeeDetails(int id,String name,String country){
this.id=id;
this.name=name;
this.country=country;
}
Try this query
To get all employee details:
SELECT new com.sample.app.model.EmployeeDetails(e.id,e.name,a.country) from Employee e,Address a
When a new address is added for a person, a new revision should be created. A revision is created, but the remaining fields of the entity in the revision are marked null.
Different and correct:
When I change a name for a person, a revision is created where all fields are entered.
Person Entity:
#Entity
#Table(name = "Person")
#Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
#Audited
public class Person implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "sequenceGenerator")
#SequenceGenerator(name = "sequenceGenerator", sequenceName = "HIBERNATE_SEQUENCE", allocationSize = 1)
private Long id;
#Column(name = "first_name")
private String firstName;
#Column(name = "last_name")
private String lastName;
#OneToMany(mappedBy="person")
#Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
private Set<Address> addresses = new HashSet<>();
Person Audit Entity:
#Entity
#Table(name = "person_aud")
#Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
public class PersonAud implements Serializable {
private static final long serialVersionUID = 1L;
#EmbeddedId
private AuditIdentity auditIdentity;
#Column(name = "revtype")
private Short revtype;
#Column(name = "first_name")
private String firstName;
#Column(name = "last_name")
private String lastName;
#ManyToOne
#MapsId("auditIdentity.id")
#JoinColumn(name = "id", nullable = false)
private Person person;
#OneToMany
#Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
private Set<Address> addresses = new HashSet<>();
Address Entity:
#Entity
#Table(name = "address")
#Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
#Audited
public class Address implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "sequenceGenerator")
#SequenceGenerator(name = "sequenceGenerator", sequenceName = "HIBERNATE_SEQUENCE", allocationSize = 1)
private Long id;
#Column(name = "street")
private String street;
#Column(name = "house_number")
private String houseNumber;
#Column(name = "zip_code")
private String zipCode;
#Column(name = "city")
private String city;
#Column(name = "state_province")
private String stateProvince;
#Column(name = "country")
private String country;
#ManyToOne
#JsonIgnoreProperties("addresses")
private Person person;
#OneToOne
#JsonIgnoreProperties("addresses")
#NotAudited
private PersonAud personAud;
If I add a new address that belongs to person XY, then my table looks like this:
PERSON_AUD:
ID: 1
REV: 1001
REVTYPE: 1
FIRST_NAME: NULL
LAST_NAME: NULL
For example, if I change the first name, the fields for the first_name and last_name are entered.
Problem solved (not perfect):
I changed the line:
#OneToMany(mappedBy="person")
#Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
private Set<Address> addresses = new HashSet<>();
to:
#OneToMany(cascade = {CascadeType.ALL})
#Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
private Set<Address> addresses = new HashSet<>();
Now the process works like:
Add a new person with empty Address array
Add a new Address which refers to the person id
Action like a PUT on this Person assigning the address-object.
= PERSON_AUD table will contain the revision and the fields.
PROBLEM:
it is not perfect because you have to assign the address manually to the person.
Is there any other possible solution?
I am working on simple spring security demo and want to put user and role info into db. Here is the simple structure of my entity.
#Entity
#Table(name = "users")
public class Users {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "user_id")
private Long userId;
#OneToMany(mappedBy = "users", fetch = FetchType.LAZY, orphanRemoval=true, cascade = CascadeType.ALL)
private List<UserRoleMapping> userRoleMapping;
}
//
#Entity
#Table(name = "user_role_mapping")
public class UserRoleMapping {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "user_role_mapping_id")
private Long userRoleMappingId;
#ManyToOne(fetch = FetchType.LAZY)
private Users users;
#ManyToOne(fetch = FetchType.LAZY)
private UserRole userRole;
}
//
#Entity
#Table(name = "users_role")
public class UserRole {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "role_id")
private Long roleId;
#Column(name = "role")
private String role;
#Column(name = "role_desc")
private String roleDesc;
#OneToMany(mappedBy = "userRole", fetch = FetchType.LAZY, orphanRemoval=true)
private List<UserRoleMapping> userRoleMapping;
}
In my use case, I have to make sure when the user is created then I have to insert subsequence userRoleMapping. And If the userRole is removed then the userRoleMapping must be deleted as well.
So I put CascadeType.ALL and orphanRemoval=true in users entity, and orphanRemoval=true in userRole entity.
However, when I run userRoleRepository.delete(userRole). I have dataIntegrityViolationException.
I did some researches on it and understand it is a kind of jpa constrains to make sure we delete the parents (users) as well.
May I ask if there are any workaround for my use case?
Thanks
Here is the solution to my use cases. Instead of using OneToMany in both entity, I should use ManyToMany relationship. And it is quite make sense as I don't care (for now) the mapping in java logic. Here is my code
public class Users {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "user_id")
private Long userId;
#ManyToMany(fetch = FetchType.LAZY, cascade = { CascadeType.MERGE, CascadeType.PERSIST })
#JoinTable
private Set<UserRole> userRole;
}
//
public class UserRole {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "role_id")
private Long roleId;
#Column(name = "role")
private String role;
#Column(name = "role_desc")
private String roleDesc;
#OneToMany(mappedBy = "userRole", fetch = FetchType.LAZY)
private Set<Users> users;
}
I use spring boot, with jpa (hibernate) and postgresql
I use composite key.
#Entity
#IdClass(SamplingsPK.class)
#Inheritance(strategy = InheritanceType.SINGLE_TABLE)
public class Samplings {
#Id
#GeneratedValue
private Integer id;
#Id
private int year;
#OneToMany(mappedBy = "sampling", cascade = CascadeType.ALL, orphanRemoval = true)
private List<Samples> samples = new ArrayList<>();
...
}
public class SamplingsPK implements Serializable {
private Integer id;
private int year;
public SamplingsPK(Integer id, int year) {
this.id = id;
this.year=year;
}
private SamplingsPK(){
}
#PrePersist
public void prePersist() {
year = LocalDate.now().getYear();
}
}
#Entity
public class Samples {
#Id
#SequenceGenerator(name = "samples_id_seq", sequenceName = "samples_id_seq", allocationSize = 1)
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "samples_id_seq")
private Integer id;
private String sampleLetter;
#ManyToOne
#JoinColumns({
#JoinColumn(name = "sampling_id", referencedColumnName = "id"),
#JoinColumn(name = "sampling_year", referencedColumnName = "year")
})
private Samplings sampling;
}
That work fine
Instead of having an sequence in samples, I would like to have a composite key... SamplingsPK + sampleLetter.
Is it possible to do it, how to save a sample?
This is a "derived identity", so Samples could be mapped with an #IdClass like this:
#Entity
#IdClass(SamplesPK.class)
public class Samples {
#Id
#ManyToOne
#JoinColumns({
#JoinColumn(name = "sampling_id", referencedColumnName = "id"),
#JoinColumn(name = "sampling_year", referencedColumnName = "year")
})
private Samplings sampling;
#Id
private String sampleLetter;
}
public class SamplesPK {
SamplingsPK sampling; // matches name of attribute and type of Samplings PK
String sampleLetter; // matches name and type of attribute
}
Derived identities are discussed (with examples) in the JPA 2.2 spec in section 2.4.1.