What is the difference between .stream() and Stream.of?

Question

Which is the best way to create a stream out of a collection:

    final Collection<String> entities = someService.getArrayList();

1. entities.stream();

2. Stream.of(entities);

Answer 1

The second one does not do what you think it does! It does not give you a stream with the elements of the collection; instead, it will give you a stream with a single element, which is the collection itself (not its elements).

If you need to have a stream containing the elements of the collection, then you must use entities.stream().