Is there a way to get a 'refreshed' saved entity when saving with JPA in Spring boot?

First of all, I am not certain if this is caching requests or otherwise just not populating fields.

I have an entity called CmsRegions, which contains the following:

public class CmsRegions extends Model implements Serializable {
       
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Basic(optional = false)
    @Column(name = "id")
    private Integer id;
    
    @Basic(optional = false)
    @NotNull
    @Size(min = 1, max = 100)
    @Column(name = "name")
    private String name;
    
    @Lob
    @Size(max = 65535)
    @Column(name = "description")
    private String description;
    
    @Size(max = 2)
    @Column(name = "lang")
    private String lang;
    
    @Size(max = 2)
    @Column(name = "locale")
    private String locale;
    
    @Basic(optional = false)
    @NotNull
    @Column(name = "is_active")
    private short isActive;
    
    @Column(name = "parent_id")
    private Integer parentId;
        
    @Basic(optional = false)
    @Column(name = "created", insertable = false, updatable = false)
    @Temporal(TemporalType.TIMESTAMP)
    private Date created;
    
    @Basic(optional = false)
    @Column(name = "modified", insertable = false, updatable = false)
    @Temporal(TemporalType.TIMESTAMP)
    private Date modified;


    ...getters and setters etc...
}

I have the basic repository call to retrieve the entity as:

@NoRepositoryBean
public interface BaseCmsRepository<T extends Serializable> extends JpaRepository<T, Long> {
    
    @Query("SELECT a FROM #{#entityName} a WHERE a.id = :id")
    List<T> getById(
            @Param("id") Integer id
    );
    

When I save the entity, it saves to the database fine into the following table:

CREATE TABLE `cms_regions` (
  `id` int unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(100) NOT NULL,
  `description` text,
  `lang` char(2) DEFAULT NULL,
  `locale` char(2) DEFAULT NULL,
  `is_active` tinyint unsigned NOT NULL DEFAULT '0',
  `parent_id` int unsigned DEFAULT NULL,
  `created` datetime DEFAULT CURRENT_TIMESTAMP,
  `modified` datetime DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=32 DEFAULT CHARSET=utf8;

The created and modified fields get set fine as expected, but the resulting entity I get from my save action, has NULL values for the created and modified dates.

I ran a test - my last insert ID was 31, so I added the following code to my controller:

    cmsService.saveRegion(region); // save entity

    CmsRegions  testreg1 = cmsService.getRegion(1);
    CmsRegions  testreg2 = cmsService.getRegion(region.getId());
    CmsRegions  testreg3 = cmsService.getRegion(30);
    CmsRegions  testreg4 = cmsService.getRegion(32);  // currently saved entity new ID (32)

When doing this - testreg1 contained the created and modified dates as Date objects as hoped. testreg2 contained null values (region.getId() = 32 at this point). testreg3 contained the Date objects for created and modified.

The final value, testreg4 was also NULL. The kicker is, next time I ran it, testreg4 had the values in it for created and modified. But the next iteration, (33) in testreg2 was once again NULL.

I do not know if this is a caching issue, or what. It just seems that if I try to pull the database value before the call has finished - EVEN though the data is now in the database (confirmed with breakpoints) - the resulting fields are always null. Next run, they are populated.

Why? What do I need to do to get these values?

When saving using JpaRepository#save or this method on any similar interface, the entity from the database is returned. You can just use it. It's most commonly used to populate the generated id:

assertNull(entity.getId());
entity = entityRepository.save(entity);
assertNotNull(entity.getId());

It's a bit more complex when the other process is changing the data and persistence context is not refreshed. Another query would be needed then. You can go around that by using EntityManager#refresh and passing the entity you would like to "refetch" from the database. Currently I don't know whether that mechanism is present in spring-data-jpa.