question: void saveOffsetInExternalStore ( String topic , int partition , long offset ) { try { FileWriter writer = new FileWriter ( storageName ( topic , partition ) , false ) ; BufferedWriter bufferedWriter = new BufferedWriter ( writer ) ; bufferedWriter . write ( offset + "" ) ; bufferedWriter . flush ( ) ; bufferedWriter . close ( ) ; } catch ( Exception e ) { e . printStackTrace ( ) ; throw new RuntimeException ( e ) ; } }
target:  Overwrite the offset for the topic in an external storage.