[hibernate-issues] [Hibernate-JIRA] Commented: (HHH-993) Criteria subquery without projection fails throwing NullPointerException

[Joachim Durchholz (JIRA)]

    [ http://opensource.atlassian.com/projects/hibernate/browse/HHH-993?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=44269#comment-44269 ] 

Joachim Durchholz commented on HHH-993:
---------------------------------------

This is particularly annoying since SubqueryExpression#createAndSetInnerQuery's method comment indicates that this is just prefetching data that it assumes will be needed later.
And, yes, it just bit me. And I'm not going to comment on how long this has been lying dormant.

> Criteria subquery without projection fails throwing NullPointerException
> ------------------------------------------------------------------------
>
>                 Key: HHH-993
>                 URL: http://opensource.atlassian.com/projects/hibernate/browse/HHH-993
>             Project: Hibernate Core
>          Issue Type: Improvement
>          Components: core
>            Reporter: Johannes Rudolph
>            Priority: Minor
>
> If you use a subquery in a criteria query and there is no projection, the execution of the query will fail by throwing a NullPointerException:
> Caused by: java.lang.NullPointerException
> at
> org.hibernate.loader.criteria.CriteriaQueryTranslator.getProjectedTypes(Crit
> eriaQueryTranslator.java:298)
> at
> org.hibernate.criterion.SubqueryExpression.toSqlString(SubqueryExpression.ja
> va:56)
> at
> org.hibernate.criterion.LogicalExpression.toSqlString(LogicalExpression.java
> :39)
> org.hibernate.loader.criteria.CriteriaQueryTranslator.getWhereCondition(Crit
> eriaQueryTranslator.java:314)
> ...
> I think it is expected behaviour that restrictions only work on 1-dimensional return values of subqueries so it would be nice if Hibernate would mention that somewhere.
> It would be nice if you could just write:
> Criteria crit = dbSession.createCriteria(Bla.class);
>         	DetachedCriteria detachedCrit = DetachedCriteria.forClass(Blub.class).add( Restrictions.eq("condition", Boolean.FALSE));
>         	crit.add( Restrictions.or( Restrictions.isNull("superBlub"), 
>         			Subqueries.in("superBlub", detachedCrit ) ) );
> since Hibernate entities could be seen as "entities" so Hibernate should automatically transform it into:
>         	DetachedCriteria detachedCrit = DetachedCriteria.forClass(Blub.class).add( Restrictions.eq("condition", Boolean.FALSE))
> .setProjection( Projections.id() );
>         	crit.add( Restrictions.or( Restrictions.isNull("superBlub"), 
>         			Subqueries.propertyIn("ueberPartner", detachedCrit ) ) );

--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira