public default Stream<E> parallelStream ()

Returns a possibly parallel Stream with this collection as its source. It is allowable for this method to return a sequential stream.

This method should be overridden when the spliterator() method cannot return a spliterator that is IMMUTABLE, CONCURRENT, or late-binding. (See spliterator() for details.)

Returns:  a possibly parallel Stream over the elements in this collection

Since:  1.8

@implSpec The default implementation creates a parallel Stream from the collection's Spliterator.