code: public static <T> com.google.common.base.Optional<T> toGuavaOptional(final Optional<T> optional) {
          return com.google.common.base.Optional.fromNullable(optional.orElse(null));
      }
docs: Convert an {@link Optional} to a Guava {@link com.google.common.base.Optional}.
  
  @param optional The {@link Optional}
  @return An equivalent Guava {@link com.google.common.base.Optional}