@Override
 public void passivate() throws Exception {
   UnitOfWork uow = uowf.newUnitOfWork();
   try {
     RootEntity root = rootEntity();
     LOGGER.info("Existing RootEntity: " + root.identity().get());
   } catch (NoSuchEntityException ex) {
     LOGGER.info("No RootEntity");
   }
   uow.complete();
 }
 @Override
 public void activate() throws Exception {
   UnitOfWork uow = uowf.newUnitOfWork();
   try {
     RootEntity root = rootEntity();
     LOGGER.info("Will use RootEntity: " + root.identity().get());
   } catch (NoSuchEntityException ex) {
     EntityBuilder<RootEntity> builder =
         uow.newEntityBuilder(RootEntity.class, RootEntity.IDENTITY);
     RootEntity root = builder.newInstance();
     LOGGER.info("Created new RootEntity: " + root.identity().get());
   }
   uow.complete();
 }