code: @Override
      public void delete(final I id) {
          if (entity != null) {
              inTransaction(
                      new Callable<Void>() {
                          @Override
                          public Void call() throws Exception {
                              final T entity = findOne(id);
                              T attached = getAttached(entity);
                              if (attached != null) {
                                  entityManager.remove(attached);
                              }
                              return null;
                          }
                      }
              );
          }
      }
docs: Deletes the given entity instance (specified by its id). The instance is removed from the persistent layer.
  
  @param id the id