How do you all feel about exposing access to the commit/optimize
callbacks in UpdateHandler? Perhaps adding the functions:
void registerCommitCallback( SolrEventListener );
void registerCommitCallback( SolrEventListener );
and/or maybe:
Collection<SolrEventListener> getCommitCollbacks();
Collection<SolrEventListener> getOptimizeCollbacks();
if the returned collection is modifiable, we could directly add to it.
Currently everything needs to be registered via solrconfig.xml -- but
I would like an UpdateProcessor to be a commit/optimize callback.
Someday we could do this with spring...