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Hibernate Envers - select "all" changes for entity ID

I have problem with Hibernate Envers.
I have classes like:
#Entity
#Table(name = "REVINFO")
#RevisionEntity(MyRevisionEntityListener.class)
public class RevEntity {
#Id
#RevisionNumber
#Column(name = "REV", nullable = false, updatable = false)
private Integer id;
#RevisionTimestamp
#Column(name = "REVTSTMP", nullable = false, updatable = false)
private Date timestamp;
#Column(name = "MODIFIED_BY", length = 100)
private String modifiedBy;
#Column(name = "COMMENT", length = 100)
private String comment;
public class MyRevisionEntityListener implements RevisionListener {
#Override
public void newRevision(Object revisionEntity) {
RevEntity a = (RevEntity) revisionEntity;
a.setComment("Some value");
}
}
How can i select every change for entity ID and their "REVINFO" object?
I've got something like this:
List resultList = AuditReaderFactory.get(entityManager)
.createQuery()
.forRevisionsOfEntityWithChanges(ClientType.class, true)
.add(AuditEntity.id().eq(entityId))
.getResultList();
And it's almost work good. I received every "change" but REVINFO looks strange. All fields are null - and there are 1 more object $$_hibernate_interceptor which actually hold "information" but i cannot acces it via code (or i dont know how). See example at the image.
So my question is:
1 - How can i get REVINFO values ?
2 - Do i realy have to use entityManager, or can it be achived with different approach ?
Edit 2:
Correct me if i am wrong, but does forRevisionsOfEntityWithChanges works as Lazy Initialization? I mean, if i try to receive for example modifiedBy field i actually get my data. Debugger log make me confused.

The call to forRevisionsOfEntityWithChanges returns an object array that contains:
Entity instance
Revision Entity
Revision Type
Property names that were changed.
How can i get REVINFO values ? 2 - Do i realy have to use entityManager, or can it be achived with different approach ?
So in your code, to get the revision info attributes, you would do the following. Note that in this code, the type of the revision-info object will depend on your configuration or if you're using a custom revision-info entity class in your deployment. Just be sure to cast it to the proper type.
for (Object entry : resultList) {
final Object[] row = (Object[]) entry;
final TheRevisionEntityClassType revisionInfo = row[1];
// now you can get the revision entity attributes from revisionInfo using getters
}
Correct me if i am wrong, but does forRevisionsOfEntityWithChanges works as Lazy Initialization? I mean, if i try to receive for example modifiedBy field i actually get my data. Debugger log make me confused.
Depending on the query, yes Hibernate may use proxies and its important to understand that in this case, the visual representation you get in the debugger may or may not be accurate depending if the object's internal state gets initialized by the debugger window or not.

Is there a way to disable fetching the entire value set for a column in Hibernate?

In our "Process" table there is a "Type" column. This column's valueset is defined in an enum in our code. However there are obsolete rows in this table. Meaning that there are rows where "type" is a value that is not present in the code's enum. The problem is whenever we acces ANY (not the obsolete ones) of the rows in this table we get an error that there is an unkown value for that column. Is there a way to disable this feature in hibernate as we do not want to delete these rows.
#EqualsAndHashCode(callSuper = true, of = {})
#Table(name = ProcessEntity.TABLE_NAME)
public class ProcessEntity extends BaseEntity implements ValidityHolder {
public static final String TABLE_NAME = "PROCESS";
#OneToMany(mappedBy = "consent", cascade = CascadeType.ALL)
private Set<ConsentAnswerEntity> consentAnswers;
#OneToMany(mappedBy = "consent", cascade = CascadeType.ALL)
private List<ProcessConsentEntity> processConsents;
#OneToMany(mappedBy = "consent", cascade = CascadeType.ALL)
private Set<ProcessTypeConsentEntity> processTypeConsents;
#Enumerated(EnumType.STRING)
#Column(name = "TYPE_ID")
private Type TpyeId;

If these "obsolete" records no longer fit into your Hibernate data model, then I recommend just moving them to some archive table. After all, you can't really select them now anyway using Hibernate, so at least at the application level, they serve no purpose.
For a more general way to logically delete a record without physically removing it, look into soft deletion. Using soft deletion, you would add a single boolean column to the table which, if marked, would indicate that the record is logically no longer there.

Why are some modifications to object lost when I merge that object in Hibernate?

Here are the relevant pieces of the code I inherited. The object "process" is the old process that is passed to the method. The object "newProcess" is what I am replacing it with, using different fields of the user's choosing.
try
{
final EntityManager em = getEntityManager();
em.getTransaction().begin();
JpaProcessDAO pDao = new JpaProcessDAO(em);
Process newProcess = pDao.findById(processId);
newProcess.setName(process.getName());
newProcess.setDataBaseVersion(process.getDataBaseVersion());
newProcess.setNotes(process.getNotes());
newProcess.setReadyForUse(process.getReadyForUse();
newProcess.setSteps(process.getSteps());
em.merge(newProcess); <---- WHERE PROBLEM OCCURS
em.persist(newProcess);
em.getTrasaction().commit();
}
RESULT: Every field that I change is changed in newProcess EXCEPT "Steps". During the merge step in the code, that list goes back to whatever the steps were in the original object "process".
Now this could be because that "Step" is an object itself, not a primitive like all of the other fields I set in "newProcess":
Mapping in Process.java
#OneToMany(mappedBy="process")
private List<Step>
// getter, setter
In Step.java there is a collection of objects, some of which are lists of nonprimitive objects themselves.
Step.java
public class Step implements Serializable {
#Id
#Column(name = "step_id")
#GeneratedValue(strategy=GenerationType.IDENTITY)
private int stepId;
private String duration;
private String name;
private String notes;
private Integer sort;
#OneToMany(mappedBy="step", cascade=CascadeType.REMOVE)
private List<Constituent> constituents;
#OneToMany(mappedBy="step")
private List<Reference> references;
#ManyToOne
#JoinColumn(name ="process_id")
private Process process;
#OneToMany(mappedBy="step",cascade=CascadeType.REMOVE)
private List<StepEquipment> stepEquipments;
public Step() {
}
// getters/setters
}
Does anybody know what this inherited code I have could possibly do wrong?
ADDITIONS TO CODE ON 11/29:
public T findById(final Integer id) throws CPDPersistenceExceptin {
return findByPrimaryKey(id,templateClass);
}
public T findBYPrimaryKey(Object key, Class<T> clazz) {
T t = getEntityManager().find(clazz,key);
getEntityManager.merge(t);
getEntityManager.refresh(t);
return t; <-------------- newProcess is returned by this statement.
}
newProcess does not have the steps that were in the original process,nor does it have the ProcessCategories that were in process. The Hibernate logs say
that select is going on for process_id, database_version, process_name, process_notes, and process_ready_to_use only in the merge and refresh statements.

You need to synchronize both sides of the association. In your code you're only setting newProcess.setSteps(...), but each Step doesn't set a Process. From here:
However, we still need to have both sides in sync as otherwise, we break the Domain Model relationship consistency, and the entity state transitions are not guaranteed to work unless both sides are properly synchronized.
So in other words, you would need to do something along the lines of:
newProcess.setSteps(process.getSteps());
process.getSteps().forEach(s -> s.setProcess(newProcess));

As in answer from dyslexit told you need to set the Process to each Step.
But in addition you need to have the new Steps persisted and old ones removed. You can do this manually per Step but easier way would be to alter your code a bit.
Mofify the mapping annotation in step like:
#OneToMany(mappedBy = "process", cascade=CascadeType.PERSIST, orphanRemoval=true)
private List<Step> steps;
so tell persist to cascade to Steps also and to remove all Steps that are detached from Process.
Modify the update logic:
// newProcess.setSteps(process.getSteps());
// em.merge(newProcess); <---- WHERE PROBLEM OCCURS
// em.persist(newProcess);
newProcess.getSteps().clear(); // remove old steps
newProcess.getSteps().addAll(process.getSteps()); // add new steps
// You need to set the other side of association also as below
newProcess.getSteps().forEach(s -> s.setProcess(newProcess));
// em.persist(newProcess); // not sure if needed
SO: do not REPLACE the list but instead MODIFY the original list.
ALSO: there might not be a need for any merge/persist operation (and certainly doing both in series is not something that should ever be done). But because you use mystical JpaProcessDAO I can not be sure so check that.
And also see for what those are really used, great explanation here.
I am guessing that entity manager might handle everything just fine - without persist/merge stuff -because I think you already got managed entity when called pDao.findById(processId);, that is why I have commented it out.
Another story is then the mappings you have in your Step class. Those might also need changes to persistence & cascade setting.
As a side note: have also a look at this question how you might have update done easier with ModelMapper.

ManyToOne Cascade causes repeated persists in the mother table

I have two entities: Questionnaire and QuestionnaireTime. Questionnaire's id is a foreign key in QuestionnaireTime. So the relationship in my QuestionnaireTime entity looks like this:
#JoinColumn(name = "questionnaireid", referencedColumnName = "id")
#ManyToOne(cascade = CascadeType.PERSIST)
private Questionnaire questionnaireid;
So what I'm trying to do is to add multiple QuestionnaireTime records for one Questionnaire. If I remove the CascadeType.PERSIST part in my relationship, my persist is not done. And when I use cascade, I get several new records in my main table Questionnaire and that's not what I want.
For example when I want to add three QuestionnaireTime's for a certain Questionnaire, the three records are inserted in my QuestionnaireTime table but also 3+1 records are added in Questionnaire.
If you need more explanation. This is my managed bean, the part that I'm trying to add multiple QuestionnaireTime records in one Questionnaire:
NB - current is my Questionnaire object
else if (current.getType().equals("frequent")) {
int iteration = 1;
currentQuestionnaireTime = new QuestionnaireTime();
if (!selectDateList.isEmpty()) {
for (String insertedDate : selectDateList) {
currentQuestionnaireTime.setId(0);
currentQuestionnaireTime.setQuestionnaireid(current);
getEjbQuestionnaireTimeFacade().create(currentQuestionnaireTime);
iteration++;
}
}
}
try {
getFacade().create(current); // my Questionnaire facade
} catch (EJBException ejbe) {
ejbe.getCause();
}

A few things,
questionnaireid - this is a very bad field name, questionnaire would make sense.
currentQuestionnaireTime.setId(0); - you should not be changing the id of an existing object, instead create a new object
getEjbQuestionnaireTimeFacade().create() - what does this do? If you need the reference to the current, then the current should be persisted first. If you EJB remote? If it is, then either make it local, or ensure you use merge() not persist(), as you new object has a reference to a detached object. Or find the reference in the current persistence context.

Refresh Hibernate Formula

I have got two entities (example reduced as much as possible; each entity has got an id field):
#Entity
public class A {
#Column(nullable = false)
private double foo;
#Formula(value = "foo - (select coalesce(sum(x.foo), 0) from x where x.a_id = id)")
private double bar;
}
and
#Entity
public class X {
#ManyToOne(optional = false)
private A a;
#Column(nullable = false)
private double foo;
}
When I create a new X (new X(), beginTransaction(), save(x), commit()) the value of A.bar is not refreshed.
I think this happens because the old (and wrong) value is still in the first level cache (there is no 2nd level cache). I dont want to call Session.clear() since this method seems to invalidate existing entity-objects. What else can I do to solve this probelm?
EDIT: As requested here is the code to save X-objects:
// setters
getSession().beginTransaction(); // getSession() returns the current session
getSession().save(entity); // entity is an instance of X
getSession().getTransaction().commit();

Session.clear will remove all the cached objects from the session. instead you can use evict method on session and specify an object, which removes only the specified object from the cache.

I tried to solve the problem with clearing the cache but that was followed up by new problems and made the cache more or less useless because Xes are changed quite often. (In fact the subselect is much more complex than shown in the question. It uses more tables.)
Now I am using the StatelessSession that does not have a first-level cache. This solves the problem. Since the database is an embedded h2-Database the performance regression is not noticeable.