code: @SuppressWarnings("unchecked")
      protected Iterable _transform(final Iterable iterable) {
          if (iterable == null) return null;
          if (iterable instanceof BeanIterable) return iterable;
          return new BeanIterable<>(iterable, this);
      }
docs: <p>_transform.</p>
  
  @param iterable a {@link java.lang.Iterable} object.
  @return a {@link java.lang.Iterable} object.