Not sure... depends on how update handlers will use it...
by update handler, you mean UpdateRequestHandler(s)? or UpdateHandler?
One thing we might not want to get rid of though is streaming (constructing and adding a document, then discarding it). People are starting to add a lot of documents in a single XML request, and this will be much larger for CVS/SQL.
So you are uncomfortable with the Collection because you would have to load all the documents before indexing them. If this was many, it could be a problem... If UpdateHandler is going to take care of stuff like autocommit and modifying documents, It seems best to have that apply to all the documents you are going to modify as a unit. For example, say i have a SQL updater that will modify 100,000 documents incrementing field 'count_*' and replacing 'fl_*'. If the DocumentCommand only applies to a single document, it would have to match each field as it went along rather then once when it starts. How about: Iterable<SolrDocument> this way, an UpdateRequestHandler can start the UpdateHandler running while it streams each document from XML/CSV/SQL ryan
