question: public void reset ( Collection < E > collection , @ Nullable DiffUtil . Callback callback ) { items . clear ( ) ; items . addAll ( collection ) ; if ( callback != null ) { updateItemsTask = new UpdateItemsTask ( ) ; updateItemsTask . execute ( callback ) ; } else { notifyDataSetChanged ( ) ; } }
target:  Resets the current adapter state - clear current items, add new ones and execute UpdateItems task.