question: @ Override public void refreshIndex ( String rowId , DimensionRow dimensionRow , DimensionRow dimensionRowOld ) { refreshIndex ( Collections . singletonMap ( rowId , new Pair < > ( dimensionRow , dimensionRowOld ) ) ) ; }
target:  Refresh lucene index Query the lucene indexes on key column to see if there are any existing indexes. If yes, then we need to update the indexes. Update is done by first deleting the existing documents and then adding new ones. If not, then just add the documents to indexes.