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Hibernate: Program run persists new created entities together with entities which were persisted in previous program run and which I had deleted

This is maybe a beginner question on hibernate. I am doing my first steps, I designed a simple datamodel consisting of about 10 entities and I use hibernate to persist them to my Oracle XE database. Now I am facing the following problem: First time, when I do a transaction to persist some entities, they are persisted properly. I verify, that the data exists in the database and then I delete all the entries from all database tables. I verify that all tables are empty again. Then I run my program again to persist some new entities - and here happens something really strange: Afterwards I find in my databse the new entries as well as the old ones, which were persisted last time and which I had deleted! They contained the old IDs and the old data fields! How can this be? This happens even if I shut down my computer after the first time the program runs! How does it remember the old entries and where are they saved? Do you have any ideas?
Some information, that might be useful:
I am using annotations (instead of config files) for the mapping.
Following you see the classes used for persisting as well as one example of an entity (I am showing only one entity to avoid making the question too long).
As you see, I am using FetchType = EAGER on my MANY to MANY mappings (as I understand, this makes sure, that all related entities are loaded immediately together with any loaded entity). Can this have any impact?
Thanks for any help!
public class PersistenceManager {
private static final SessionFactory factory = new Configuration().configure().buildSessionFactory();
public static void sampleData() {
try(Session session = factory.openSession()) {
SampleDataLoader.loadSampleData(session);
} catch(HibernateException e) {
System.out.println("Exception during persisting! Message: " + e.getMessage());
e.printStackTrace();
}
}
}
public class SampleDataLoader {
static void loadSampleData(Session session) {
Language french = new Language("French");
Language german = new Language("German");
Noun garcon = new Noun(french, "garcon", false);
Noun junge = new Noun(german, "Junge", false);
junge.addTranslation(garcon);
ZUser user = new ZUser("Daniel", "password");
user.setOwnLanguage(german);
user.setEmail("abc#somemail.de");
user.setDateRegistered(LocalDateTime.now());
user.addForeignLanguage(french);
Transaction transaction = session.beginTransaction();
session.save(user);
session.save(french);
session.save(german);
session.save(junge);
transaction.commit();
}
}
#Entity
public class ZUser {
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
#Column(name = "id")
private int id;
#Column
private String name;
#Column
private String password;
#Column
private String email;
#Column
private String picturePath;
#Column
private LocalDateTime dateRegistered;
#ManyToOne(fetch=FetchType.EAGER)
#JoinColumn(name="OWNLANGUAGE_ID")
private Language ownLanguage;
#ManyToMany(cascade = { CascadeType.ALL })
#JoinTable(name="USER_LANGUAGE",
joinColumns=#JoinColumn(name="USER_ID"),
inverseJoinColumns=#JoinColumn(name="LANGUAGE_ID")
)
private Set<Language> foreignLanguages = new HashSet<>();
public ZUser() { }
public ZUser(String n, String p) {
name = n;
password = p;
}
public int getId() { return id; }
public void setId(int id) { this.id = id; }
public String getName() { return name; }
public void setName(String name) { this.name = name; }
public String getPassword() { return password; }
public void setPassword(String password) { this.password = password; }
public String getEmail() { return email; }
public void setEmail(String email) { this.email = email; }
public String getPicturePath() { return picturePath; }
public void setPicturePath(String picturePath) { this.picturePath = picturePath; }
public LocalDateTime getDateRegistered() { return dateRegistered; }
public void setDateRegistered(LocalDateTime dateRegistered) { this.dateRegistered = dateRegistered; }
public Language getOwnLanguage() { return ownLanguage; }
public void setOwnLanguage(Language ownLanguage) { this.ownLanguage = ownLanguage; }
public void addForeignLanguage(Language language) {foreignLanguages.add(language);}
public Set<Language> getForeignLanguages() {return Collections.unmodifiableSet(foreignLanguages); }
}

Clarified by the comment of Jagger (see comments). Indeed, I was using Oracle SQL command line to delete the entries and I had rgotten, that I need to explicitely commit after deleting. The solution can be so easy :)

Hibernate call DELETE from table after method end

I have problem, and I don't know how to solve it.
I have entity:
#Entity
#Table(name = "entity_languagetree")
#AttributeOverride(name = "id", column = #Column(name = "languagetree_id"))
public class LanguageTree extends BaseObject {
#ElementCollection(targetClass = java.lang.String.class, fetch = FetchType.EAGER)
#CollectionTable(name = "view_languagetree_to_stringlist")
private List<String> relationship = new ArrayList<>();
public LanguageTree() {
//
}
public List<String> getRelationship() {
return relationship;
}
public void setRelationship(List<String> relationship) {
this.relationship = relationship;
}
}
where BaseObject is
#MappedSuperclass
public class BaseObject {
#Id
#GeneratedValue
#Column(name = "entity_id")
private Long id;
/**
*
* #return true if the entity hasn't been persisted yet
*/
#Transient
public boolean isNew() {
return id == null;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public Bean getBean() {
return null;
}
}
Work with object - in my servlet, I am calling jsVarTree() like this:
String var = jsVarTree();
My problem is, that after method jsVarTree is finished, hibernate delete my relationship list from entity LanguageTree. I don't know why! I am not calling any delete and etc.. (I AM SURE, I SPENT A LOT OF TIME IN DEBUGER!)
:
#Override
public String jsVarTree() {
TreeBuilder tb = new TreeBuilder(getLanguageList());
return tb.getJsVarString(); // THIS METHOD IS ONLY GETTER !!!!
}
#Override
public List<String> getLanguageList() {
LanguageTree lt = getLanguageTreeObject();
return lt.getRelationship();
}
#Override
public LanguageTree getLanguageTreeObject() {
long fakingId = languageTreeDao.getLastId();
ServerLogger.logDebug("LAST FAKING ID: " +fakingId);
return languageTreeDao.findOne(fakingId);
}
I found this log in loggor:
HibernateLog --> 15:01:03 DEBUG org.hibernate.SQL - delete from
view_languagetree_to_stringlist where LanguageTree_languagetree_id=?
Can somebody tell me, why hibernate call delete over my table?
I saw a table in phpmyadmin..
TABLE IS FULL.
String var = jsVarTree();
TABLE IS EMPTY.
Table is deleted after return tb.getJsVarString(); is finished.
Thank you for any help!

findRecord in Google CloudDatastore with Objectify

I want to use Objectify to query Google Cloud Datastore. What is an appropriate way to find a record based on a known key-value pair? The record is in the database, I verified this by Google's Datastore viewer.
Here is my method stub, which triggers the NotFoundException:
#ApiMethod(name="getUser")
public User getUser() throws NotFoundException {
String filterKey = "googleId";
String filterVal = "jochen.bauer#gmail.com";
User user = OfyService.ofy().load().type(User.class).filter(filterKey, filterVal).first().now();
if (user == null) {
throw new NotFoundException("User Record does not exist");
}
return user;
}
Here is the User class:
#Entity
public class User {
#Id
Long id;
private HealthVault healthVault;
private String googleId;
public User(String googleId){
this.googleId = googleId;
this.healthVault = new HealthVault();
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public HealthVault getHealthVault() {
return healthVault;
}
public void setHealthVault(HealthVault healthVault) {
this.healthVault = healthVault;
}
public String getGoogleId() {
return googleId;
}
public void setGoogleId(String googleId) {
this.googleId = googleId;
}
}

I think it fails because of transaction. You need to make a transctionless call like:
User user = OfyService.ofy().transactionless().load().type(User.class).filter(filterKey, filterVal).first().now();
More info about transactions on App Engine:
https://cloud.google.com/appengine/docs/java/datastore/transactions
https://github.com/objectify/objectify/wiki/Transactions
EDIT
Your object needs #Index annotation. It will add field to datastore index. Only properties that are in the index can be searchable. Filter method is one of them.
#Id
Long id;
#Index
private HealthVault healthVault;
#Index
private String googleId;
P.S. delete your object with googleId jochen.bauer#gmail.com and write it again to database after you updated your entity. And objectify will find it.

First add #Index in your fields model. I didn't see filterVal as an email in your model. Even so, to get the entity based in your filterVal assuming that is googleId is the field of your entity.
User user = OfyService.ofy().load().type(User.class).filter("googleId", filterVal).now();
And so if your filterKey is the id of your entity.
User user = OfyService.ofy().load().key(Key.create(User.class, filterKey)).now();

Hibernate optimistic locking using version is not working

I am trying to use optimistic locking using the version field and no exception is being thrown when I call the save from the jpa repository. I am new to Spring and hibernate and I am worried that I am setting it up incorrectly.
The libraries i am using are:
hibernate4-maven-plugin version 1.0.2
hibernate-jpa02.0 1.0.1
spring-data-jpa version 1.3.4
So my entity is set up like this:
#Entity
public class MyEntity
{
#Id
protected Long id;
#Version
protected Long version;
protected String name;
public Long getVersion()
{
return version;
}
public void setVersion(Long version)
{
this.version = version;
}
public Long getVersion()
{
return version;
}
public void setVersion(Long version)
{
this.version = version;
}
public Long getId()
{
return id;
}
public void setId(Long id)
{
this.id = id;
}
public String getName()
{
return name;
}
public void setName(Long id)
{
this.name = name;
}
}
I pass the version through to the client through my dto and pass it back when i do a save in my MyEntityStoreDao:
#Repository
public class MyEntityStoreDao extends BaseDao<MyEntityStoreDao>
{
private RepositoryManager myRepoManager;
#Autowired
public void setMyRepo(MyEntityRepository myRepo)
{
this.myRepo = myRepo;
}
public MyEntity save(MyEntityDTO dtoToUpdate)
{
Session session = this.Session();
MyEntity myEntity = new MyEntity();
if(dtoToUpdate.getId() > 0) {
myEntity = (MyEntity) session.get(MyEntity.class, dtoToUpdate.getId())
}
myEntity.setName(dtoToUpdate.getName());
MyEntity result = this.myRepo.save(myEntity);
this.repositoryManager.flush(myRepo);
}
}
The repositoryManager is in the BaseDao and is using the org.springframework.data.jpa.repository.JpaRepository.
The version is being updated correctly and incrementing. But when i do an update, I expect when the version being passed through from the DTO to save in the MyEntityStoreDao to not match what is in the database, it would throw a StaleStateException or OptmisticLockingException.
I checked and the versions do not match but the save still occurs. Any help on why this is happening? Thanks

Turn On sql logging by show-sql=true and see if the update query has the required where clause
where version = ?
If such where clause is missing then you need to add annotation #org.hibernate.annotations.Entity(dynamicUpdate = true)

With your updated Code
MyEntity myEntity = new MyEntity(); // You dont need to initalize
if(dtoToUpdate.getId() > 0) {
myEntity = (MyEntity) session.get(MyEntity.class, dtoToUpdate.getId())
}
myEntity.setName(dtoToUpdate.getName());
MyEntity result = this.myRepo.save(myEntity);
you are trying to save the myEntity , Which has recent information (correct version) from database. So you will not get any error. if you want to produce the error please do the following..
public MyEntity save(MyEntityDTO dtoToUpdate)
{
Session session = this.Session();
MyEntity myEntityV1 = null;
MyEntity myEntityV2 = null;
// Getting v1 and V2. at this time both V1 & V2 will have same version ( assume version as 5)
if(dtoToUpdate.getId() > 0) {
myEntityV1 = (MyEntity) session.get(MyEntity.class, dtoToUpdate.getId()) ;
myEntityV2 = (MyEntity) session.get(MyEntity.class, dtoToUpdate.getId()) ;
}
myEntityV1.setName(dtoToUpdate.getName());
// Saving V1 will reflect the increase in version ( actual row will be version of 6)
MyEntity result = this.myRepo.save(myEntityV1);
myEntityV2.setName("some changes"); // change some in V2instance. So that hibernate/Jpa will capture the change
this.myRepo.save(myEntityV2); // You will get exception. because the v2 has version as 5. but the row was updated .
this.repositoryManager.flush(myRepo);
}
So basically when you update the entity in Db, if the entity version (variable in object) is not equal to the version ( field in the table) in database ( before this update) it will throw exception

OUT OF MEMORY in hibernate

Hi I have created many to one relationship in hibernate.
Following is the code for that.
there are thousands of records present in B table which is link to single record of table A. When i used getBList() method it will returns thousands of record and JAVA goes OUT OF MEMORY.
So how can i solve this problem.
#Entity
#Table(name = "A")
public class A {
private int Id;
private String aName;
private List<MksReleaseInfo> bList;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "id")
public int getId() {
return releaseId;
}
public void setId(final int Id) {
this.Id = Id;
}
#Column(name = "aname", unique = true)
public String getAName() {
return aName;
}
public void setAName(final String aName) {
this.aName = aName;
}
#OneToMany(mappedBy = "aName")
public List<MksReleaseInfo> getBList() {
return bList;
}
public void setBList(final List<B> bList) {
this.bList = bList;
}
}
#Entity
#Table(name = "B")
public class B {
private int bIndex;
private int bpriority;
private A aName;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "id")
protected int getBIndex() {
return mksReleaseInfoIndex;
}
protected void setBIndex(final int bIndex) {
this.bIndex = bIndex;
}
#Column(name = "priority")
public int getBPriority() {
return bpriority;
}
public void setBPriority(final int bpriority) {
this.bpriority = bpriority;
}
#ManyToOne
#JoinColumn(name = "Id")
public A getAName() {
return aName;
}
public void setAName(final A aName) {
this.aName = aName;
}
}
after all the comments i have implemented the following code. but again it gives OUT OF MEMORY. Should i have to flush the memory explicitly and how?
public List<B> getList(String name, int offset, int limit) throws DAOException {
try {
String hql = "from B where name = :name";
begin();
Query query = getSession().createQuery(hql);
query.setString("name", name);
if(offset > 0){
query.setFirstResult(offset);
}
if(limit > 0){
query.setMaxResults(limit);
query.setFetchSize(limit);
}
commit();
return query.list();
} catch (HibernateException e) {
rollback();
}
}
public Long countB(String name) throws DAOException {
try {
String hql = "select count(*) from B where name = :name";
begin();
Query query = getSession().createQuery(hql);
query.setString("name", name);
commit();
return (Long)query.uniqueResult();
} catch (HibernateException e) {
rollback();
}
}
long count = countB(name);
int counter = (int) (count / 200);
if(count%200 > 0){
counter++;
}
for(int j = 0;j<counter;j++){
lists = getList(name, j*200, 200);
for(B count1 : lists){
System.out.println(count1);
}
}

You could introduce a DAO in order to retrieve the records from B given a A object in a paged way.
For example:
public interface BDao {
Page findByA(A a, PageRequest pageRequest);
}
Maybe you could take an idea from approach taked in Spring Data

Set MaxResults property of datasource, it will set limit on number of records you are getting.
Also, you can increase java heap memory size using -Xmx256m. This will set maximum heap allocation size to 256MB. You can set it as you need.

You can use query with paging for this purpose. In Query class you can find setFirstResult and setMaxResults methods which can help you to iterate over records. If you need to load all B objects and store them you can adjust memory settings of java by setting -Xmx option. Also you can try to declare some kind of reduced class B (for example ReducedB), which contains only required fields, and use iterating with converting B to ReducedB to reduce memory usage.
Also you can check this question. I think that it is close enought to what you want.
P.S. Final solution would depend on particular issue that you want to solve.

I had the same issue. I looked at my code and server space but nothing helped. Later I looked into data and realized wrongly placed data was making application use lot of processing power. Make sure you do not have duplicated data in child class.