I want to use in my spring application with spring data set of enums, which will be stored in db. Currently i tried it in that way:
#NotNull
#Column(name = "ROLES")
#Enumerated(EnumType.STRING)
#ElementCollection(targetClass = Role.class)
private Role role;
#NotNull
#Column(name = "PERMISSIONS")
#Enumerated(EnumType.STRING)
#ElementCollection(targetClass = Permission.class)
private Set<Permission> permissions;
but as you propably know it do not work. How can i use enums to be stored in db?
Best regards!
You should add #CollectionTable anotation with specified name and join column.
May this will work for you.
#ElementCollection(targetClass = Permission.class)
#CollectionTable(name = "permissions", joinColumns = #JoinColumn(name = "permission_id"))
#Column(name = "permission", nullable = false)
#Enumerated(EnumType.STRING)
Set<Permission> permission;
Related
I am struggling with the following problem that I've been trying to solve. After checking solutions on StackOverflow and articles on Baeldung I still get different JPA errors when trying to map the following ONE-TO-ONE relationship between 2 Oracle SQL tables with composite PK in a SpringBoot application:
MASTER
ID
VERSION
1
2022.1
Constraint:
PK_MASTER PRIMARY KEY(ID, VERSION)
MASTER_DETAILS
MASTER_ID
VERSION
DETAILS
1
2022.1
details
Constraint:
PK_MASTER_DETAILS PRIMARY KEY(MASTER_ID, VERSION)
FK_MASTER_DETAILS FOREIGN KEY(MASTER_ID, VERSION) REFERENCES MASTER(ID, VERSION)
After some failures in trying to map it using the #OneToOne JPA annotation with both classes having #EmbeddedId set on the composite PK, I also installed JPA Buddy to check how it will be generated and that resulted in the following 4 classes:
Master.java
#Getter
#Setter
#Entity
#Table(name = "master")
public class Master {
#EmbeddedId
private MasterId id;
#OneToOne(mappedBy = "master")
private MasterDetails masterDetails;
}
MasterId.java
#Getter
#Setter
#Embeddable
public class MasterId implements Serializable {
private static final long serialVersionUID = 8254837075462858051L;
#Column(name = "id", nullable = false)
private BigDecimal id;
#Lob
#Column(name = "version", nullable = false)
private String version;
}
MasterDetails.java
#Getter
#Setter
#Entity
#Table(name = "master_details")
public class MasterDetails {
#EmbeddedId
private MasterDetailsId id;
#MapsId
#OneToOne(fetch = FetchType.LAZY, optional = false)
#JoinColumns({
#JoinColumn(name = "master_id", referencedColumnName = "id", nullable = false),
#JoinColumn(name = "version", referencedColumnName = "version", nullable = false)
})
private Master master;
#Lob
#Column(name = "details", nullable = false)
private String details;
}
MasterDetailsId.java
#Getter
#Setter
#Embeddable
public class MasterDetailsId implements Serializable {
private static final long serialVersionUID = -8375336118866998644L;
#Column(name = "master_id", nullable = false)
private BigDecimal masterId;
#Lob
#Column(name = "version", nullable = false)
private String version;
}
When running the SpringBoot application with this JPA structure the run time error received is:
org.hibernate.PropertyNotFoundException: Could not locate field [id] on class [org.project.packages.MasterDetails]
After removing the #MapsId that cause this error the application starts but when trying to insert data in the tables I get the following error:
org.hibernate.id.IdentifierGenerationException: null id generated for:class org.project.packages.MasterDetails
Checking in the H2 test database I noticed that the FK on the Master_Details table was not present, but only the PK was set.
I would appreciate any help in pointing out how this problem can be solved: other annotations required (Cascade/FetchType) or in case there are any changes to be made to the database level (I also tried adding a separate identifier column in the Master_Details table defined as PK and only keep the FK to the Master table). Thanks in advance!
After many tries, I figured out to solve the issue.
I had to use a common key between the two entities and also FetchType.LAZY.
MasterDetails.class
public class MasterDetails {
#EmbeddedId
#AttributeOverrides({
#AttributeOverride(name="ID", column=#Column(name="MASTER_ID"))
})
private MasterId id;
#OneToOne(fetch = FetchType.LAZY, optional = false)
#JoinColumns({
#JoinColumn(name = "master_id", referencedColumnName = "id", nullable = false),
#JoinColumn(name = "version", referencedColumnName = "version", nullable = false)
})
private Master master;
#Lob
#Column(name = "guidance", nullable = false)
private String guidance;
}
Master.class
public class MasterSheet {
#EmbeddedId
private MasterId id;
#OneToOne(mappedBy = "master", fetch = FetchType.LAZY, cascade = CascadeType.ALL)
private MasterDetails masterDetails;
}
I started to learn spring data rest. I'm doing PUT operation and it's not working for the nested objects for ManyToMany relationship, whereas it works fine for OneToMany relation.
Entities structures:
#Table(name="CONFIG_DTLS",schema = "app_txn")
#Entity
public class Config {
#Id
#GenericGenerator(name = "UUIDGenerator", strategy = "uuid2")
#GeneratedValue(generator = "UUIDGenerator")
#Column(name = "ID", updatable = false, nullable = false)
private UUID id;
#Column(name = "NAME", nullable = false, length = 75)
private String name;
/*Unable to replace the data in the MBR_CONFIG_MAPPING table in the put operation.
When the control comes to #HandleBeforeSave annotated method in PUT operation,
the request data contains the existing Member info instead of the one which i'm passing in the PUT request body */
#ManyToMany(cascade = {CascadeType.PERSIST, CascadeType.MERGE},fetch = FetchType.EAGER)
#JoinTable(schema = "app_txn", name = "MBR_CONFIG_MAPPING",
joinColumns ={#JoinColumn(name="CONFIG_ID",referencedColumnName = "ID")},
inverseJoinColumns = {#JoinColumn(name="MBR_ID",referencedColumnName = "ID")}
)
private Set<Member> members;
//able to replace the notifications completely in PUT operation
#OneToMany(cascade = CascadeType.ALL,fetch = FetchType.EAGER)
#JoinColumn(name = "CONFIG_ID",referencedColumnName = "ID")
private Set<Notification> notifications;
}
Member.java
#Table(name="MBR_DTLS",schema = "app_txn")
#Entity
public class Member {
#Id
#GenericGenerator(name = "UUIDGenerator", strategy = "uuid2")
#GeneratedValue(generator = "UUIDGenerator")
#Column(name = "ID", updatable = false, nullable = false)
private UUID id;
#Column(name = "OTHER_MBR_DATA", updatable = false)
private String otherMbrData;
}
Notification.java
#Table(name="NOTIFICATIONS",schema = "app_txn")
#Entity
public class Notification {
#Id
#GenericGenerator(name = "UUIDGenerator", strategy = "uuid2")
#GeneratedValue(generator = "UUIDGenerator")
#Column(name = "ID", updatable = false, nullable = false)
private UUID id;
#Column(name="LEVEL")
private String level;
#Column(name="EMAIL")
private String email;
}
Interfaces:
#RepositoryRestResource(collectionResourceRel = "configs", path="configs")
public interface ConfigRepo extends PagingAndSortingRepository<Config,UUID> {
}
#RepositoryRestResource(exported=false) // don't want to users to manipulate it directly.
public interface MemberRepo extends PagingAndSortingRepository<Member,Object> {
}
Here I don't want to add or modify anything in the MBR_DTLS table as it is loaded by another backend process. I want to update only the mapping details MBR_CONFIG_MAPPING table whenever user does the PUT/update operation. POST/create operation is working fine. Please share your thoughts on how to fix this and if you have any questions add it in the comment section.
PS: I referred some links online but that does not help much - Spring Data REST - PUT request does not work properly since v.2.5.7
I want to convert this sql query to a JPA query, but I can't seem make sense of it... Should I use findByMarinaIdAndMovementGroupMeanId?? or findByMarinaIdAndMovementGroupMeanIdAndMovementMeanId??
Sql:
select m.* from movement_group m
join movement_group_mean mgm on m.id = mgm.movement_group_id
join movement_mean mm on mgm.movement_mean_id = mm.id
where mm.id = 1 and m.marina_id = :marinaId and mm.active = true;
MovementGroup:
#Entity
public class MovementGroup {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private String name;
private String code;
private LocalDateTime createdAt;
private LocalDateTime updatedAt;
private Boolean active;
private String iconUrl;
#OneToMany(mappedBy = "movementGroup")
private Set<MovementGroupMean> movementGroupMeans;
#JsonIgnore
#ManyToOne()
#JoinColumn(name = "marina_id")
private Marina marina;
MovementGroupMean:
#Entity
public class MovementGroupMean {
#EmbeddedId
#JsonIgnore
private MovementGroupMeanPK movementGroupMeanPK;
#JsonBackReference
#ManyToOne
#JoinColumn(name = "movement_group_id", insertable = false, updatable = false)
private MovementGroup movementGroup;
#ManyToOne
#JoinColumn(name = "movement_mean_id", insertable = false, updatable = false)
private MovementMean movementMean;
MovementMean:
#Entity
public class MovementMean {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private String name;
#Enumerated(EnumType.STRING)
private MovementMeanType movementMeanType;
private Boolean active;
private LocalDateTime createdAt;
private LocalDateTime updatedAt;
#JsonBackReference
#ManyToOne()
#JoinColumn(name = "marina_id")
private Marina marina;
Not sure where the problem lies, so excuse the lengthy explanation on SQL->JPQL:
Replace your table names with your entity names
movement_group -> MovementGroup
Replace your joins with the java references, letting JPA use the relationship mapping you've defined instead.
"join movement_group_mean mgm on m.id = mgm.movement_group_id" becomes "join m.movementGroupMeans mgm"
"join movement_mean mm on mgm.movement_mean_id = mm.id becomes "join mgm.movementMean mm"
Only tricky spot is your entities do not define a basic mapping for the marina_id value. So to get at m.marina_id, you will have to use the 'marina' reference and use its presumably ID value:
"m.marina_id = :marinaId" -> "m.marina.id = :marinaId"
Giving you JPQL:
"Select m from MovementGroup m join m.movementGroupMeans mgm join mgm.movementMean mm where mm.id = 1 and m.marina.id = :marinaId and mm.active = true"
Job entity
#Column(name = "name")
private String name;
#ManyToMany
#JoinTable(name = "user_job",
joinColumns = #JoinColumn(name = "job_id"),
inverseJoinColumns = #JoinColumn(name = "user_id")
)
private List<User> user;
User entity
#Column(name = "email")
private String email;
#ManyToMany
#JoinTable(name = "user_job",
joinColumns = #JoinColumn(name = "user_id"),
inverseJoinColumns = #JoinColumn(name = "role_id")
)
private Set<Role> roles;
Role entity
#Column(name = "name")
private String name;
#ManyToMany(mappedBy = "roles")
private Set<User> users;
Here we have a table user_job with 3 ids and I want to insert data in service layer. How I can do it and what repository I should implement or use existent like user/role/job?
class UserJobService{
public void setUserJob(User user, Job job, Role role){
}
}
The problem with #ManyToMany association is you can't delete a record directly from user_job table, using Hibernate. To delete the record, you need to load a user with all his jobs. So better to add UserJobEntity
#Entity
#Table(name = "USER_JOBS")
class UserJobEntity {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "ID")
private Long id;
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "USER_ID")
private User user;
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "JOB_ID")
private Job job;
}
public UserJobEntity createUserJob(UserEntity user, JobEntity job) {
UserJobEntity userJob = new UserJobEntity();
userJob.setUser(user);
userJob.setJob(job);
return userJobRepository.save(userJob);
}
Probably you will want to add (user, job) unique constraint to user_jobs table.
Some advices
Use plurals for table names. user_jobs in place of user_job
Role is tabular data. So it shouldn't have a users List.
Don't use Set for associated collections. Definitely you will encounter "multiple bugs fetch exception" and this exception will help you to change queries. With Set you can have large cross products and even don't notice them.
I am developing an application for vehicle stock tracking system using spring boot, angular and mysql. Multiple images of the vehicle will be loaded from the interface. Normally, when there is only one image, I define a field of type byte [] with #lob annotation. But how can I keep it in the database when more than one image comes in. I think a relational structure is required but I couldn't.
public class User extends BaseEntity{
#Column(name = "TC_NUM", unique = true)
#NotNull
private String tcNum;
#Column(name = "EMAIL", unique = true)
#NotNull
private String email;
#Column(name = "USERNAME", unique = true)
#NotNull
private String username;
#Column(name = "PASSWORD")
#NotNull
private String password;
#ManyToMany(fetch = FetchType.EAGER)
#JoinTable(name = "User_ROLES",
joinColumns = #JoinColumn(name = "USER_ID"), inverseJoinColumns = #JoinColumn(name = "ROLE_ID"))
#NotNull
private Set<Role> roles;
}
Yes, you need to have One to Many relation.
Add another db table and entity for vehicle images. Let's say we called it VehicleImage:
#Entity
#Table(name="vehicle_image")
public class VehicleImage{
#Id
private Long id;
#Lob
#Column(name = "image", columnDefinition="BLOB")
private byte[] image;
#ManyToOne(fetch = FetchType.LAZY)
private User user;
public VehicleImage() {}
// getters and setters
}
And add mapping to your User class like that:
public class User extends BaseEntity{
#OneToMany(
mappedBy = "user",
cascade = CascadeType.ALL,
orphanRemoval = true
)
private Set<VehicleImage> vehicleImages;
public void addVehicleImage(VehicleImage vehicleImage) {
vehicleImages.add(vehicleImage);
vehicleImage.setUser(this);
}
public void removeVehicleImage(VehicleImage vehicleImage) {
vehicleImages.remove(vehicleImage);
vehicleImage.setUser(null);
}
//rest of your class
}
As you can see I've also added two utility methods to User class. For details, see this great post by Vlad Mihalcea -> https://vladmihalcea.com/the-best-way-to-map-a-onetomany-association-with-jpa-and-hibernate/
Now you can persist your images like that:
User user = new User();
user.addVehicleImage(
new VehicleImage (imageBytesArray)
);
entityManager.persist(user);