Hi,

I noticed something strange using DetachedCriteria with subqueries: Listing the outer DetachedCriteria produces a NPE unless the inner DetachedCriteria is listed first.

This kind of defeats to purpose of DetachedCriteria for me, because I need access to the session while assembling the DetachedCriteria.

Is anyone aware of another workaround? An even better solution would be a join inside the employees subquery, but that's currently not possible AFAIK.

Any ideas?

Thanks, Dan.


Hibernate version: 3.0.5
Code between sessionFactory.openSession() and session.close():
Session session = // ...

DetachedCriteria addresses = DetachedCriteria.forClass(Address.class);
addresses.add(Restrictions.eq("city", "chicago"));
addresses.setProjection(Projections.property("id"));

DetachedCriteria employees = DetachedCriteria.forClass(Employee.class);
employees.add(Property.forName("address").in(addresses));
employees.setProjection(Projections.property("department"));

DetachedCriteria departments = DetachedCriteria.forClass(Department.class);
departments.add(Property.forName("id").in(employees));

Criteria crit = departments.getExecutableCriteria(session);

// unless this method is called before crit.list(),
// Hibernate fails with a NPE, see below
employees.getExecutableCriteria(session).list();

List result = crit.list();

Full stack trace of any exception that occurs:
java.lang.NullPointerException
at org.hibernate.criterion.SubqueryExpression.getTypedValues(SubqueryExpression.java:80)
at org.hibernate.loader.criteria.CriteriaQueryTranslator.getQueryParameters(CriteriaQueryTranslator.java:231)
at org.hibernate.criterion.SubqueryExpression.toSqlString(SubqueryExpression.java:55)
at org.hibernate.loader.criteria.CriteriaQueryTranslator.getWhereCondition(CriteriaQueryTranslator.java:314)
at org.hibernate.loader.criteria.CriteriaLoader.<init>(CriteriaLoader.java:92)
at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1303)
at org.hibernate.impl.CriteriaImpl.list(CriteriaImpl.java:300)
...

Database schema:
TABLE DEPARTMENT
-ID
-NAME

TABLE EMPLOYEE
-ID
-NAME
-DEPT_ID
-ADDRESS_ID

TABLE ADDRESS
-ID
-STREET
-CITY

Are joins in Criteria subqueries fixed in the latest 3.1. Gavin suggested that he was going to work on this in a previous posting and couldn't located in JIRA.

Cheers,
Roll