docs: private void setPrefix(final Future<Void> aFuture) {
          if (LOGGER.isDebugEnabled()) {
              LOGGER.debug(MessageCodes.PT_DEBUG_033, myPath);
          }
  
          myFileSystem.writeFile(getPrefixFilePath(), Buffer.buffer(myPrefix.get()), result -> {
              if (result.succeeded()) {
                  aFuture.complete();
              } else {
                  aFuture.fail(result.cause());
              }
          });
      }