docs: void roll() {
          m_batchLock.writeLock().lock();
          final PeriodicExportContext previous = m_current;
          try {
              m_current = new PeriodicExportContext();
  
              m_logger.trace("Rolling batch.");
  
              for( ExportToFileDecoder decoder : m_tableDecoders.values()) {
                  decoder.resetWriter();
              }
  
          }
          finally {
              m_batchLock.writeLock().unlock();
          }
          previous.closeAllWriters();
      }