Filtering by JPAExpressions.type throws IllegalArgumentException

[bekoeppel]

In a model with Single Table Inheritance, I would like to select objects based on their type. For this, I use the JPAExpressions.type expression:

    JPAQuery query = new JPAQuery(entityManager);
    query.from(parent)
        .where(JPAExpressions.type(parent).in(typeList)
    );

However, when my typeList is a List<String> of class names, I get:

    java.lang.IllegalArgumentException: Parameter value [ChildA] did not match expected type [java.lang.Class (n/a)]
    at org.hibernate.jpa.spi.BaseQueryImpl.validateBinding(BaseQueryImpl.java:874)
    at org.hibernate.jpa.internal.QueryImpl.access$000(QueryImpl.java:80)
    at org.hibernate.jpa.internal.QueryImpl$ParameterRegistrationImpl.bindValue(QueryImpl.java:248)
    at org.hibernate.jpa.internal.QueryImpl$JpaPositionalParameterRegistrationImpl.bindValue(QueryImpl.java:337)
    at org.hibernate.jpa.spi.BaseQueryImpl.setParameter(BaseQueryImpl.java:674)
    at org.hibernate.jpa.spi.AbstractQueryImpl.setParameter(AbstractQueryImpl.java:198)
    at org.hibernate.jpa.spi.AbstractQueryImpl.setParameter(AbstractQueryImpl.java:49)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.springframework.orm.jpa.SharedEntityManagerCreator$DeferredQueryInvocationHandler.invoke(SharedEntityManagerCreator.java:311)
    at com.sun.proxy.$Proxy99.setParameter(Unknown Source)
    at com.mysema.query.jpa.impl.JPAUtil.setConstants(JPAUtil.java:55)
    at com.mysema.query.jpa.impl.AbstractJPAQuery.createQuery(AbstractJPAQuery.java:128)
    at com.mysema.query.jpa.impl.AbstractJPAQuery.createQuery(AbstractJPAQuery.java:94)
    at com.mysema.query.jpa.impl.AbstractJPAQuery.list(AbstractJPAQuery.java:245)
    at ch.benediktkoeppel.test.querydsltype.ParentRepositoryCustomImpl.findByType(ParentRepositoryCustomImpl.java:18)
    ...

I think the typeList should be List<Class>, but the method signature does not allow this.

It could also be that I use the JPAExpressions.type wrongly. I asked a question on StackOverflow but did not get an answer: http://stackoverflow.com/questions/34568368/where-condition-based-on-jpas-type-with-querydsl

[gkprasad0308]

I am also struggling with this issue, did we have any solution to solve this problem?

[manorfm]

...
where(parent.instanceOfAny([QTypeA.getType(), QTypeB.getType()]))
...

[jwgmeligmeyling]

Try Expressions.operation(Class.class, JPQLOps.TYPE, parent).in(typeList).

I agree that JPAExpressions.type could have returned this result for you, but that probably gives new issues when its used in the select clause of a query.