Spring data JPA entity change not being persisted - spring

Question

I have a Spring data entity (using JPA w/ Hibernate and MySQL) defined as such:
#Entity
#Table(name = "dataset")
public class Dataset {
#Id
#GenericGenerator(name = "generator", strategy = "increment")
#GeneratedValue(generator = "generator")
private Long id;
#Column(name = "name", nullable = false)
private String name;
#Column(name = "guid", nullable = false)
private String guid;
#Column(name = "size", nullable = false)
private Long size;
#Column(name = "create_time", nullable = false)
private Date createTime;
#OneToOne(optional = false)
#JoinColumn(name = "created_by")
private User createdBy;
#Column(name = "active", nullable = false)
private boolean active;
#Column(name = "orig_source", nullable = false)
private String origSource;
#Column(name = "orig_source_type", nullable = false)
private String origSourceType;
#Column(name = "orig_source_org", nullable = false)
private String origSourceOrg;
#Column(name = "uri", nullable = false)
private String uri;
#Column(name = "mimetype", nullable = false)
private String mimetype;
#Column(name = "registration_state", nullable = false)
private int registrationState;
#OneToMany(fetch = FetchType.EAGER, cascade = {CascadeType.ALL})
#JoinColumn(name = "dataset_id")
#JsonManagedReference
private List<DatasetFile> datasetFiles;
I have the following repository for this entity:
public interface DatasetRepo extends JpaRepository<Dataset, Long> {
#Query("SELECT CASE WHEN COUNT(p) > 0 THEN 'true' ELSE 'false' END FROM Dataset p WHERE p.uri = ?1 and p.registrationState>0")
public Boolean existsByURI(String location);
#Query("SELECT a FROM Dataset a LEFT JOIN FETCH a.datasetFiles c where a.registrationState>0")
public List<Dataset> getAll(Pageable pageable);
#Query("SELECT a FROM Dataset a LEFT JOIN FETCH a.datasetFiles c WHERE a.registrationState>0")
public List<Dataset> findAll();
#Query("SELECT a FROM Dataset a LEFT JOIN FETCH a.datasetFiles c where a.guid= ?1")
public Dataset findByGuid(String guid);
}
Now - In a controller, I am fetching a dataset, updating one of its attributes and I would be expecting that attribute change to be flushed to the DB, but it never is.
#RequestMapping(value = "/storeDataset", method = RequestMethod.GET)
public #ResponseBody
WebServiceReturn storeDataset(
#RequestParam(value = "dsGUID", required = true) String datasetGUID,
#RequestParam(value = "stType", required = true) String stType) {
WebServiceReturn wsr = null;
logger.info("stType: '" + stType + "'");
if (!stType.equals("MongoDB") && !stType.equals("Hive") && !stType.equals("HDFS")) {
wsr = getFatalWebServiceReturn("Invalid Storage type '" + stType + "'");
} else if (stType.equals("MongoDB")) {
/* Here is where I'm reading entity from Repository */
Dataset dataset = datasetRepo.findByGuid(datasetGUID);
if (dataset != null) {
MongoLoader mongoLoader = new MongoLoader();
boolean success = mongoLoader.loadMongoDB(dataset);
logger.info("Success: " + success);
if (success) {
/* Here is where I update entity attribute value, this is never flushed to DB */
dataset.setRegistrationState(1);
}
wsr = getWebServiceReturn(success ? 0 : -1, "Successfully loaded dataset files into " + stType + " storage", "Failed to load dataset files into " + stType + " storage");
}
}
return wsr;
}
Thank you

Answer 1

You need to annotate the method of request mapping with #Transactional.
Why? If you want to modify an object in memory and then it is updated transparently in the database you need do it inside an active transaction.
Don't forget you're using JPA (spring-data is using JPA) and if you want your Entity will be in a managed state you need an active transaction.
See:
http://www.objectdb.com/java/jpa/persistence/update
Transparent Update Once an entity object is retrieved from the
database (no matter which way) it can simply be modified in memory
from inside an active transaction:
Employee employee = em.find(Employee.class, 1);
em.getTransaction().begin();
employee.setNickname("Joe the Plumber");
em.getTransaction().commit();