AND/OR grouping WHERE conditions with Criteria Predicates in Hibernate

Question

I am having an issue with grouping my WHERE conditions. Ultimately, my goal is to have groups of AND conditions, each of which is an OR. For example:

SELECT *
WHERE ( foo = 1 AND bar = 2) 
OR (foo = 3 AND bar = 4)
OR (foo = 5 AND bar = 6)

Below is the code that I am using to accomplish this. As you can see, I am creating 2 'equal' Predicates, and then am creating a Predicate which nests them.

List<Waybill> getWaybillsByCriteriaOrderItemList(List< OrderItem > orderItems ) {
    CriteriaBuilder cb = em.getCriteriaBuilder()
    CriteriaQuery<Waybill> q = cb.createQuery( Waybill )
    Root<Waybill> waybillRoot = q.from(Waybill)
    q.select( waybillRoot )
    List<Predicate> predicates = []


    orderItems.each { OrderItem item ->
        Predicate carInit = cb.equal( cb.trim(waybillRoot.get('carInit')), item.carInit)
        Predicate carNumb = cb.equal( cb.trim(waybillRoot.get('carNumb')), item.carNum )
        Predicate thisCar = cb.or (
                cb.and( carInit ),
                cb.and( carNumb )
        )
        predicates << thisCar
    }
    q.where(predicates.toArray(new Predicate[predicates.size()]))
    TypedQuery<Waybill> tq = em.createQuery(q)
    List<Waybill> result = tq.getResultList()
    result
}

Unfortunately, the AND/OR grouping is exactly the opposite of what I would expect. Here is the generated HQL

select generatedAlias0 from Waybill as generatedAlias0 where 
( ( trim(BOTH   from generatedAlias0.carInit)=:param0 ) or ( trim(BOTH   from generatedAlias0.carNumb)=:param1 ) ) 
and 
( ( trim(BOTH   from generatedAlias0.carInit)=:param2 ) or ( trim(BOTH   from generatedAlias0.carNumb)=:param3 ) ) 
and
( ( trim(BOTH   from generatedAlias0.carInit)=:param4 ) or ( trim(BOTH   from generatedAlias0.carNumb)=:param5 ) ) 

Simply reversing those and() and or() methods did not solve my issue either. It resulted in everything being AND like so:

 Predicate thisCar = cb.and (
     cb.or( carInit ),
     cb.or( carNumb )
 )

~~~~

select generatedAlias0 from Waybill as generatedAlias0 where 
( ( trim(BOTH   from generatedAlias0.carInit)=:param0 ) and ( trim(BOTH   from generatedAlias0.carNumb)=:param1 ) )
and
( ( trim(BOTH   from generatedAlias0.carInit)=:param2 ) and ( trim(BOTH   from generatedAlias0.carNumb)=:param3 ) )
and
( ( trim(BOTH   from generatedAlias0.carInit)=:param4 ) and ( trim(BOTH   from generatedAlias0.carNumb)=:param5 ) )

I have tried every combination that I can think of. Can anyone point out what it is that I am doing wrong?

Answer 1

Try to change:

Predicate thisCar = cb.or (
            cb.and( carInit ),
            cb.and( carNumb )
    );

to:

Predicate thisCar = cb.and( carInit , carNumb );

And after the loop, add the or statement to the array of predicates:

q.where(cb.or(predicates.toArray(new Predicate[] {})));