Does lucene support on the fly creation of new cores

[KK <di...@gmail.com>]

Hi All,
I've been using solr and I was trying to register new cores on the fly but
due to some issues with the latest solr1.3 I'm not able to do so. I'm using
solrJ for posting docs to solr. Now I want to know does lucene support
multiple indexes, I think yes, it does support. Can anyone tell me how to
register/create new cores on the fly. I'm just starting to use lucene and I
think all these creation of docs and posting to solr will all be in Java,
right? Can some one give/point to some examples for the same. And yes how
difficult/easier it will be for a solr and solrJ user to switch to lucene?
an estimate on this?

Thanks,
KK.