code: @NullSafe
    public static <T> Iterable<T> nullSafeIterable(Iterable<T> iterable) {
      return iterable != null ? iterable : emptyIterable();
    }
docs: Null-safe method returning the given {@link Iterable} or an empty {@link Iterable} if null.
  
  @param <T> Class type of the elements in the {@link Iterable}.
  @param iterable {@link Iterable} to evaluate.
  @return the given {@link Iterable} or an empty {@link Iterable} if null.
  @see #emptyIterable()
  @see java.lang.Iterable