code: @Override
      public void close()
      {
          try {
              flush();
              indexWriter.close();
          }
          catch (MutationsRejectedException e) {
              throw new PrestoException(UNEXPECTED_ACCUMULO_ERROR, "Mutation was rejected by server on close", e);
          }
      }
docs: Flushes all remaining mutations via {@link Indexer#flush} and closes the index writer.