Hi,

We have a parent-child relationship in our indexed domain objects, and all child and parent fields are in the same Lucene index.

Specifically, we have:

• AbstractItem
• PhysicalItem extends AbstractItem
• DigitalItem extends AbstractItem
• IntellectualItem extends AbstractItem

The concrete classes all have the identical annotation:

We are including facets in our search, and a search needs to return all item types (i.e., instances of PhysicalItem, DigitalItem and IntellectualItem).

However, for constructing the QueryBuilder in order to construct a FacetingRequest, we can only specify a single entity. This can't be AbstractItem as it's abstract, so we are currently - arbitrarily - picking one of the subclasses.

So:

For a search, this returns identical facet results regardless which subclass I use in forEntity() but the technique seems a bit odd and fragile. I suspect this is currently working fine because all of the subclasses are using the same Lucene index.

So, my questions are:

1. Is this approach indeed a bit suspect?
2. Is there a better approach? (I see that there is a TODO in QueryContextBuilder that there should be a forEntities() method written)

I guess if I wanted to be really safe I could construct separate faceting requests for each subclass, but this seems like a reasonable amount of bother...

Thanks,
Matt

Hi,



Yes. It works, but a QueryContextBuilder#forEntities and maybe a QueryContextBuilder#forIndex should be added to create a more intuitive API.
This should mirror a little how you for example can access IndexReaders. There is a IndexReaderAccessor#open(Class<?>... entities) and IndexReaderAccessor#open(String... indexNames).



Not at the moment. It really needs someone to implement the TODOs. We are always looking for some helping hands :-)

--Hardy

Lovely, thanks Hardy. Believe me - I'd be very happy to contribute to the Hibernate Search codebase if I had the time :(