I have an entity like this
#Entity
#Getter
#NoArgsConstructor
public class Order {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#Embedded
private ItemList itemList;
}
#Embeddable
public class ItemList {
#OneToMany(cascade = CascadeType.ALL)
#JoinColumn(name = "order_id")
private List<Item> itemList;
}
When I try to get ItemList using queryDSL below:
JPAQueryFactory query = new JPAQueryFactory(entityManager);
QOrder o = QOrder.order;
return query.select(o.itemList)
.from(o)
.fetch();
It generates the error...
Index 0 out of bounds for length 0
java.lang.ArrayIndexOutOfBoundsException: Index 0 out of bounds for length 0
Is there a way to select Embeddable class directly at queryDSL?
Related
Parent data is saving but list of children data is not saving in table.
data from postman
{"billno":"nur-1001", "grandTotal": 5000,"billcart":[{"itemcode":"SU10027", "soldPrice":0},{"itemcode":"SU10027","soldPrice":1100}]}
Bill is parent Entity & billcart is child entity
#NoArgsConstructor #AllArgsConstructor #Data #Entity
public class Bill {
#Id
#GeneratedValue(strategy=GenerationType.IDENTITY)
private Long id;
private String billno;
private Long grandTotal;
#OneToMany(mappedBy = "bill", cascade = CascadeType.ALL)
#JsonIgnore
private List<Billcart> billcart = new ArrayList<>();
public Bill( String billno, Long grandTotal, List<Billcart> billcart) {
this.billno = billno;
this.grandTotal = grandTotal;
this.billcart = billcart;
this.billcart.forEach(e -> e.setBill(this));
}
}
child entity
#NoArgsConstructor #AllArgsConstructor #Data #Entity
public class Billcart {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private String itemcode;
private Integer soldPrice;
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "bill_id")
private Bill bill;
controller
public void saveBill(#RequestBody Bill request) {
List<Billcart> billscart = request.getBillcart().stream()
.map(e -> new Billcart(e))
.collect(Collectors.toList());
Bill bill = new Bill(request.getBillno(), request.getGrandTotal() , billscart);
billRepository.save(bill);
i want to implement a many to many association with quantity information in it . like this :
#Entity
#Table(name = "reserves")
#Getter #Setter #NoArgsConstructor
public class Reserve {
#Id
#ManyToOne(cascade = CascadeType.ALL,fetch = FetchType.EAGER)
#JoinColumn(name = "groupe_id")
private GroupeSanguin bloodGroup;
#Id
#ManyToOne(cascade = CascadeType.ALL,fetch = FetchType.EAGER)
private Banque banque;
private int quantity;
}
the GroupSanguin and the Banque are two class stored in the database two . here is the code for the two if you need :
#Entity
#Table(name = "groupe_sanguins")
public class GroupeSanguin {
#Id
private String groupe;
#OneToMany(mappedBy = "groupeSanguin")
private List<Donneur> donneurs;
}
#Entity #Getter #Setter #NoArgsConstructor
public class Banque {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#Column(unique = true,nullable = false)
private String nom;
private String adresse;
#Column(unique = true)
private String telephone;
private String localisation;
}
so my i want to know how to annotate the JpaRepository to take the two as primary key like this and is my annotation good for it to work ?
public interface ReserveRepository extends JpaRepository<
Reserve,
//what to put here ?
>
This isn't a JPA question in fact, it's a relationnal database conception.
If Reserve has is own data and links with other entity it has it own Id
You can add unicity constraint
#Entity
#Table(name = "reserves", uniqueConstraints={
#UniqueConstraint(columnNames = {"banque_id", "groupe_id"})
#Getter #Setter #NoArgsConstructor
public class Reserve {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#ManyToOne(cascade = CascadeType.ALL,fetch = FetchType.EAGER)
#JoinColumn(name = "groupe_id")
private GroupeSanguin bloodGroup;
#ManyToOne(cascade = CascadeType.ALL,fetch = FetchType.EAGER)
#JoinColumn(name = "banque_id")
private Banque banque;
private int quantity;
}
i've found this solutions too.
#Entity
#Table(name = "reserves")
#Getter #Setter #NoArgsConstructor
#IdClass(ReserveId.class) //this annotation will tell that id that the
// the id will be represented by a class
public class Reserve {
#Id
#ManyToOne(cascade = CascadeType.ALL,fetch = FetchType.EAGER)
#JoinColumn(name = "groupe_id")
private GroupeSanguin groupeSanguin;
#Id
#ManyToOne(cascade = CascadeType.ALL,fetch = FetchType.EAGER)
#JoinColumn(name = "banque_id")
private Banque banque;
private int quantity;
}
and the id class should implements Serializable like this :
#Getter #Setter
public class ReserveId implements Serializable {
private Banque banque;
private GroupeSanguin groupeSanguin;
}
and finally the repository will be like that :
#Repository
public interface ReserveRepo extends JpaRepository<Reserve, ReserveId>{}
See your Reserve class has nowhere mentioned composite primary key. First you need to fix the model, You can refer to the solution here How to create and handle composite primary key in JPA
#Getter #Setter #NoArgsConstructor #AllArgsConstructor
#Table(name = "my_users")
public class MyUsers {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(nullable = false)
private Long id;
#Column(nullable = false, unique = true)
private String userName;
private String password;
#ManyToMany
private List<MyUsers> connections;
}
This is my MyUsers Model Class. I am using Hibernate and MySQL.
#ManyToMany
private List<MyUsers> connections;
This ManyToMany relationship is automatically creating the table 'my_users_connections' with 'my_users_id' and 'connections_id' colums. How can I add extra columns to this auto mapped table?
It's not ideal solution...
#Getter
#Setter
#NoArgsConstructor
#AllArgsConstructor
#Entity
#Table(name = "my_users")
public class MyUsers implements Serializable {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(nullable = false)
private Long myUsersId;
#Column(nullable = false, unique = false)
private String userName;
private String password;
#ManyToMany(cascade = CascadeType.ALL)
#JoinTable(name = "my_users_connections",
joinColumns = { #JoinColumn(name = "my_users_id") },
inverseJoinColumns = { #JoinColumn(name = "connections_id") })
private List<MyUsers> connections;
}
Create embedded id MyUsersConnectionsPK:
#Data
#Embeddable
public class MyUsersConnectionsPK implements Serializable {
#Column(name = "my_users_id")
private Long myUsersId;
#Column(name = "connections_id")
private Long connectionsId;
}
Create MyUsersConnections, which represent ManyToMany
#Data
#Entity
#Table(name = "my_users_connections")
public class MyUsersConnections implements Serializable {
#EmbeddedId
private MyUsersConnectionsPK id;
#ManyToOne
#MapsId("my_users_id")
#JoinColumn(name = "my_users_id")
private MyUsers myUsersId;
#ManyToOne
#MapsId("connections_id")
#JoinColumn(name = "connections_id")
private MyUsers connectionsId;
#Column(name = "extra_column")
private String extraColumn;
}
Create JPA repository
#Repository
public interface MyUsersConnectionsRepository extends JpaRepository<MyUsersConnections, MyUsersConnectionsPK> {
List<MyUsersConnections> findMyUsersConnectionsByMyUsersIdMyUsersId(Long id);
}
And simple sample for using:
#Service
public class Test {
#Autowired
private MyUsersConnectionsRepository myUsersConnectionsRepository;
#Autowired
private MyUsersRepository myUsersRepository;
public void test() {
MyUsers myUsers = new MyUsers();
myUsers.setUserName("user name");
myUsers.setPassword("password");
MyUsers myUsers2 = new MyUsers();
myUsers2.setUserName("user name 2");
myUsers2.setPassword("password 2");
myUsers.setConnections(Collections.singletonList(myUsers2));
myUsers = myUsersRepository.saveAndFlush(myUsers);
List<MyUsersConnections> myUsersConnections = myUsersConnectionsRepository.findMyUsersConnectionsByMyUsersIdMyUsersId(myUsers.getMyUsersId());
MyUsersConnections item = myUsersConnections.get(0);
item.setExtraColumn("Extra column");
myUsersConnectionsRepository.saveAndFlush(item);
}
}
I'm trying to have Spring Data JPA issue one query using joins to eagerly get a graph of entities:
#Entity
#NamedEntityGraph(name = "PositionKey.all",
attributeNodes = {#NamedAttributeNode("positionKey.account"),
#NamedAttributeNode("positionKey.product")
})
#Data
public class Position {
#EmbeddedId
private PositionKey positionKey;
}
#Embeddable
#Data
public class PositionKey implements Serializable {
#ManyToOne
#JoinColumn(name = "accountId")
private Account account;
#ManyToOne
#JoinColumn(name = "productId")
private Product product;
}
Here's my Spring Data repo:
public interface PositionRepository extends JpaRepository<Position, PositionKey> {
#EntityGraph(value = "PositionKey.all", type = EntityGraphType.LOAD)
List<Position> findByPositionKeyAccountIn(Set<Account> accounts);
}
This produces the following exception:
java.lang.IllegalArgumentException: Unable to locate Attribute with the the given name [positionKey.account] on this ManagedType
I want all of the accounts and products to be retrieved in one join statement with the positions. How can I do this / reference the embedded ID properties?
I would suggest refactoring the entity this way if it possible
#Entity
#NamedEntityGraph(name = "PositionKey.all",
attributeNodes = {#NamedAttributeNode("account"),
#NamedAttributeNode("product")
})
#Data
public class Position {
#EmbeddedId
private PositionKey positionKey;
#MapsId("accountId")
#ManyToOne
#JoinColumn(name = "accountId")
private Account account;
#MapsId("productId")
#ManyToOne
#JoinColumn(name = "productId")
private Product product;
}
#Embeddable
#Data
public class PositionKey implements Serializable {
#Column(name = "accountId")
private Long accountId;
#Column(name = "productId")
private Long productId;
}
Such an EmbeddedId is much easier to use. For instance, when you are trying to get an entity by id, you do not need to create a complex key containing two entities.
I have 2 tables Employee & EmployeeAddress joined by one to many relationship with Foreign key. When i am trying to save the Employee object i am getting the below log in my console. It might be this unidirectional joining is not happening properly.
2019-07-26 16:32:19 - SQL Error: 1048, SQLState: 23000
2019-07-26 16:32:19 - Column 'EMP_ID' cannot be null
Below are POJO Classes: These are mapped with the DB tables.I am facing issues with the Join column.
Can any one please help me on this.
Thanks in advance.
Try using:
#OneToMany(cascade = {CascadeType.PERSIST, CascadeType.MERGE})
Assuming the issue is with Relationship so please make sure the following is correct
mappedBy is used on the parent Entity and have the same name
reference in Child Entity
use cascade = CascadeType.PERSIST, cascade = CascadeType.ALL or cascade = CascadeType.MERGE (sometime) at Parent Entity
#JoinColumn is used on Child Entity with correct reference column of Parent
Parent.java
#Entity
#Table(name = "parent")
#Getter
#Setter
#AllArgsConstructor
#NoArgsConstructor
#ToString
public class Parent {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private int parentId;
private String name;
#OneToMany(mappedBy="parent",fetch=FetchType.LAZY,cascade = CascadeType.PERSIST)
private List<Child> child = new ArrayList<Child>();
}
Child.java
#Entity
#Table(name = "child")
#Getter
#Setter
#AllArgsConstructor
#NoArgsConstructor
#ToString
public class Child {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private int childId;
private String account;
#ManyToOne(fetch = FetchType.LAZY, targetEntity = Parent.class)
#JoinColumn(name="parentId", referencedColumnName = "parentId", nullable = false)
private Parent parent;
}
Controller
#RestController
public class RelationshipController {
#Autowired ParentRepository parentRepository;
#Autowired ChildRepository childRepository;
//save Child with Parent at same
#PostMapping(value = "/onetomany")
public String OneToMany(#RequestBody Parent parent)
{
for (Child child : parent.getChild()) {
child.setParent(parent);
}
parent.setChild(parent.getChild());
parentRepository.save(parent);
return "saved";
/*{
"name":"Romil",
"child":[
{"account":"1"},
{"account":"2"}
]
}*/
}
//save Child with Parent's ID
#PostMapping(value = "/onetomanyPID")
public String OneToMany(#RequestBody Child child)
{
child.setParent(child.getParent());;
childRepository.save(child);
return "saved";
/*{
"account":"3",
"parent":{
"parentId":"1",
"name":"Romil"
}
}*/
}
}