question: public long addCompletedBatch ( RequestBatch requestBatch ) { long completedBatchId = insertBatchAsCompleted ( requestBatch ) ; for ( Request request : requestBatch . getRequests ( ) ) { request . setBatchId ( completedBatchId ) ; File file = new File ( request . getDestinationPath ( ) ) ; long length = file . exists ( ) ? file . length ( ) : 0 ; insertRequestAsCompletedDownload ( request . getDestinationPath ( ) , length , request ) ; } return completedBatchId ; }
target:  Adds this batch to the downloads system.