> I'm late to the discussion
Yes, I didn't leave much time for debate I really wanted to get back to something backward compatible so I could update Solr to use the latest Lucene.
> but it seems invalid to me. Won't getField() get a class cast exception
Yes, as I noted here:
But only if you are using the new Field options. That's the price to pay for backward compatibility, but it's a much better alternative than breaking everyones code when it's not necessary.
> it would have to do type testing on the members of fields.
The JVM does this for us
> Searchable was the same kind of thing.
I don't recall if it did breack backward compatibility, but even so... how many people write their own Searchers/IndexReaders vs how many people call Document.getField()?