getDocValues should provide a MultiReader DocValues abstraction
---------------------------------------------------------------

                 Key: LUCENE-1789
                 URL: https://issues.apache.org/jira/browse/LUCENE-1789
             Project: Lucene - Java
          Issue Type: Improvement
            Reporter: Hoss Man
            Priority: Minor
             Fix For: 2.9


When scoring a ValueSourceQuery, the scoring code calls 
ValueSource.getValues(reader) on *each* leaf level subreader -- so DocValue 
instances are backed by the individual FieldCache entries of the subreaders -- 
but if Client code were to inadvertently  called getValues() on a MultiReader 
(or DirectoryReader) they would wind up using the "outer" FieldCache.

Since getValues(IndexReader) returns DocValues, we have an advantage here that 
we don't have with FieldCache API (which is required to provide direct array 
access). getValues(IndexReader) could be implimented so that *IF* some a caller 
inadvertently passes in a reader with non-null subReaders, getValues could 
generate a DocValues instance for each of the subReaders, and then wrap them in 
a composite "MultiDocValues".




-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


---------------------------------------------------------------------
To unsubscribe, e-mail: java-dev-unsubscr...@lucene.apache.org
For additional commands, e-mail: java-dev-h...@lucene.apache.org

Reply via email to