Method cycle

guava/src/com/google/common/collect/Iterables.java:374–392

Returns an iterable whose iterators cycle indefinitely over the elements of {@code iterable}. <p>That iterator supports {@code remove()} if {@code iterable.iterator()} does. After {@code remove()} is called, subsequent cycles omit the removed element, which is no longer in {@code iterable}. The ite

(Iterable<T> iterable)

   * Stream.generate(() -> iterable).flatMap(Streams::stream)}.
   */
  public static <T extends @Nullable Object> Iterable<T> cycle(Iterable<T> iterable) {
    checkNotNull(iterable);
    return new FluentIterable<T>() {
      @Override
      public Iterator<T> iterator() {
        return Iterators.cycle(iterable);
      }

      @Override
      public Spliterator<T> spliterator() {
        return Stream.generate(() -> iterable).<T>flatMap(Streams::stream).spliterator();
      }

      @Override
      public String toString() {
        return iterable.toString() + " (cycled)";
      }
    };
  }

  /**
   * Returns an iterable whose iterators cycle indefinitely over the provided elements.