Javassist dependency conflict in the ORM modules for WildFly
by Sanne Grinovero
Hi all,
there's a conflict in the Javassist versions of the WildFly modules of
Hibernate ORM 5.2.4.Final, but I'm not sure how to proceed as I'm not
familiar with this functionality.
The module declares *both*:
- a dependency to the WildFly provided Javassist: <module
name="org.javassist"/>
- inclusion of Hibernate's own version of Javassist: <resource-root
path="javassist-3.20.0-GA.jar"/>
Having both is causing trouble as they are both visible to the
Hibernate classloader; however I couldn't score a quick win with the
testsuiste by disabling either (all tests using these modules in the
Hibernate Search testsuite fail).
I suspect the problem is that JipiJapa also depends on the <module
name="org.javassist"/>, while ORM obviously needs the more recent
version of it.
I'm not familiar with what JipiJapa's business around Javassist; could
we keep the two clearly separated?
Especially if we want to make Byte Buddy a viable alternative, I
suspect the solution is that JipiJapa should not depend on Javassist
directly, but invoke a generic instrumentation SPI on Hibernate; also
with JipiJapa not able to see Javassist at all, we'd be in control of
the one and only Javassist version visible to ORM: the one we compile
and test with.
Thanks,
Sanne
7 years, 7 months
HHH-11144
by Gail Badner
HHH-11144 involves an entity that has 2 one-to-many associations with the
same type of entity, and both associations have orphanRemoval = true.
Andrea created a PR with test case at [1]
I am not sure if this is a valid mapping. I I would like your thoughts on
this.
Here is an excerpt of the relevant bits:
@Entity(name = "Item")
public static class Item {
@OneToMany(mappedBy = "parent", cascade = CascadeType.ALL, orphanRemoval
= true)
protected Set<ItemRelation> lowerItemRelations = new LinkedHashSet<>();
@OneToMany(mappedBy = "child", cascade = CascadeType.ALL, orphanRemoval =
true)
protected Set<ItemRelation> higherItemRelations = new LinkedHashSet<>();
}
@Entity(name = "ItemRelation")
public static class ItemRelation {
@ManyToOne(optional = false)
@JoinColumn(name = "PARENT_ID")
private Item parent;
@ManyToOne(optional = false)
@JoinColumn(name = "CHILD_ID")
private Item child;
}
HHH-11144 describes inconsistent behavior observed when
Item#lowerItemRelations and Item#higherItemRelations both contain the same
ItemRelation, then one of the collections is cleared.
If the non-cleared collection is uninitialized, then the ItemRelation is
orphan deleted.
If the non-cleared collection is initialized, then the orphan-deleted
ItemRelation is rescued when PERSIST_ON_FLUSH cascades to the non-cleared
collection elements. The next time the collections are loaded from the
database, both will still contain that same ItemRelation.
The spec says:
"Portable applications must otherwise not depend upon a specific order of
removal, and must not reassign an entity that has been orphaned to another
relationship or *otherwise attempt to persist it*"
Is Hibernate doing the right thing by rescuing an orphan-deleted entity?
In addition, this mapping allows a particular EntityRelation to be
associated with 2 different Item entities, which would mean that the same
ItemRelation would have 2 different owners with respect to orphan deletion..
The spec says:
"The orphanRemoval functionality is intended for entities that are privately
“owned” by their parent entity."
Does this mean that the mapping is invalid, since it would allow multiple
parent entities, or does it mean that the resulting behavior is undefined
(thus non-portable)?
Please let me know your thoughts.
Thanks,
Gail
[1] https://github.com/hibernate/hibernate-orm/pull/1607
7 years, 8 months
dynamic instantiation queries
by Steve Ebersole
Historically (well before JPA) HIbernate would handle dynamic instantiation
queries in cases where one of the arguments being an entity-reference by
passing just the entity's identifier rather than a complete reference to
the entity. To be clear, I am talking about a query like:
select new DTO( p ) from Person p
Hibernate implicitly treats this like:
select new DTO( p.id ) from Person p
and expects DTO to have a ctor taking the appropriate ID type.
JPA came along and also defines support for dynamic instantiation queries,
but does not specify one way or the other how this case should be handled.
I have been told other providers interpret this the opposite way. Makes
sense. I think it is time we at least allow that as an option. Or maybe a
nicer implementation that looks for both and picks the available one (if
that's not too much effort).
What do y'all think?
7 years, 9 months
6.0 - ResultTransformer
by Steve Ebersole
Another legacy concept I'd like to revisit as we move to 6.0 is the
Hibernate ResultTransformer. I'd argue that ResultTransformer is no longer
needed, especially in it's current form.
Specifically, ResultTransformer defines 2 distinct ways to transform the
results of a query:
1. `#transformTuple` - this method operates on each "row" of the result,
allowing the user to transform the Object[] into some other structure.
This is specifically the one I see no value in moving forward. Between
dynamic-instantiation, Tuple-handling, etc I think users have the needed
capabilities to transform the query result tuples.
2. `#transformList` - this one operates on the query result as a whole
(unless scroll/iterate are used). This method at least adds something that
cannot be done in another way. But I'd still personally question its
overall usefulness.
Does anyone have an argument for continuing to support either of these?
Personally, I propose just dropping the ResultTransformer support
altogether.
7 years, 9 months
RH Summit 2017 CFP
by Chris Cranford
The Red Hat Summit 2017 CFP is closing on December 16th and I would
recommend we try and submit our abstracts this week if we could. From
the ORM side, is there any particular topics we'd care to present or
anyone who would like to present?
Chris
7 years, 11 months
Use @AssociationOverride with @MapKeyJoinColumn
by Florian Lacreuse
Hi,
We have a problem using @AssociationOverride and @MapKeyJoinColumn and
we would like to have your opinion about this to know if this is an issue.
Here is the test case :
https://github.com/florianlacreuse/hibernate-test-case
Short explanation about the model : an entity with an embeddable field
wrapping a map with an entity as key and a basic type as value.
We use @AssociationOverride to rename the join table (annotation on
embeddable field) and @MapKeyJoinColumn to rename the column related to
the key map (annotation on map field).
Unfortunately, it would seem that the @MapKeyJoinColumn annotation is
ignored. @AssociationOverride may override any other annotations on the
map field ? In this case how to rename the column related to the key map
with the @AssociationOverride ?
Is this an issue or is there any trick we don't know about?
Thanks for your help.
Kind regards,
Logo <http://www.smile.fr/>
151 boulevard Stalingrad
69100 Villeurbanne
www.smile.fr <http://www.smile.fr/>
*Florian LACREUSE*
Ingénieur d'études et développement
Pôle Développement Spécifique Java
Open Wide - Systèmes d'Information
Email : florian.lacreuse(a)smile.fr <mailto:florian.lacreuse@smile.fr>
7 years, 12 months
