In the following issue, Gavin King says that can use foo.class in (...) as an instanceof operator. How? Any example?

http://opensource.atlassian.com/project ... se/HB-1470

Thanks

I went looking for this myself and had a guess at the syntax - for anyone else looking this worked for me as an example:

superclass.class in(SubClass)

So for a very basic example:

from Wheel wheel
left outer join wheel.car
where car.class in(Subaru)

this would find all wheels for Subarus. This is taken from a much more complicated query that i've tried to extract the important parts from but I think that would work. It gives an idea of the syntax at least.

"The special property class accesses the discriminator value of an instance in the case of polymorphic persistence. A Java class name embedded in the where clause will be translated to its discriminator value." - from JBoss documentation

The following HQL will return only superclass instances. You can probably also use "not in(MySubClass1 , MySubClass2)", but I haven't tried that.

"select model from MySuperclass model where model.class != MySubClass1 and model.class != MySubClass2"

I have confirmed that the following HQL will return only instances of the superclass:

"select model from MySuperclass model where model.class not in(MySubClass1, MySubClass2, MySubClass3)"